M
Math Coach Amy
Amy Ferguson Moncure

H Algebra 2/Trig · Unit 2

Convert to Standard Form

Start in root form or vertex form. Expand the parenthesis and multiply the binomials. When a is not 1, combine like terms inside the parentheses before you distribute.

Jump to section:

What to Remember

Root form

Root form is y = a(x − r)(x − s).

The parentheses are already binomials.

Vertex form

Vertex form is y = a(x − h)² + k.

Expand the parenthesis: (x − h)² = (x − h)(x − h).

Add k after you distribute a.

Four steps

Expand the parenthesis.

Multiply the binomials.

When a is not 1, combine like terms inside the parentheses.

Distribute the a-value.

Combine any like terms that are left.

Standard form

Standard form is y = ax² + bx + c.

One x² term, one x term, and one constant.

Easy 1

Root → Standard, a = 1

Expand the parenthesis. Multiply the binomials. Distribute the a-value. Combine like terms.

Example
Write in standard form. y = (x − 3)(x + 1)

Expand the parenthesis.

y = a(x − r)(x − s)

y = (x − 3)(x + 1)

Multiply the binomials.

(x − 3)(x + 1)

x² + x − 3x − 3

Distribute the a-value.

a = 1

y = 1(x² + x − 3x − 3)

y = x² + x − 3x − 3

Combine like terms.

x − 3x = −2x

y = x² − 2x − 3

Answer: y = x² − 2x − 3

1
Write in standard form. y = (x − 6)(x − 2)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = (x − 6)(x − 2)

Multiply the binomials.

(x − 6)(x − 2)

x² − 2x − 6x + 12

Distribute the a-value.

a = 1

y = 1(x² − 2x − 6x + 12)

y = x² − 2x − 6x + 12

Combine like terms.

−2x − 6x = −8x

y = x² − 8x + 12

Answer: y = x² − 8x + 12

2
Write in standard form. y = (x + 4)(x − 1)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = (x + 4)(x − 1)

Multiply the binomials.

(x + 4)(x − 1)

x² − x + 4x − 4

Distribute the a-value.

a = 1

y = 1(x² − x + 4x − 4)

y = x² − x + 4x − 4

Combine like terms.

−x + 4x = 3x

y = x² + 3x − 4

Answer: y = x² + 3x − 4

3
Write in standard form. y = (x + 5)(x + 2)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = (x + 5)(x + 2)

Multiply the binomials.

(x + 5)(x + 2)

x² + 2x + 5x + 10

Distribute the a-value.

a = 1

y = 1(x² + 2x + 5x + 10)

y = x² + 2x + 5x + 10

Combine like terms.

2x + 5x = 7x

y = x² + 7x + 10

Answer: y = x² + 7x + 10

4
Write in standard form. y = (x − 7)(x + 3)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = (x − 7)(x + 3)

Multiply the binomials.

(x − 7)(x + 3)

x² + 3x − 7x − 21

Distribute the a-value.

a = 1

y = 1(x² + 3x − 7x − 21)

y = x² + 3x − 7x − 21

Combine like terms.

3x − 7x = −4x

y = x² − 4x − 21

Answer: y = x² − 4x − 21

5
Write in standard form. y = x(x + 8)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = x(x + 8)

Multiply the binomials.

x(x + 8)

x² + 8x

Distribute the a-value.

a = 1

y = 1(x² + 8x)

y = x² + 8x

Combine like terms.

y = x² + 8x

Answer: y = x² + 8x

Easy 2

Vertex → Standard, a = 1

Expand the parenthesis. Multiply the binomials. Distribute the a-value. Combine like terms.

Example
Write in standard form. y = (x − 4)² + 1

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 4)²

(x − 4)(x − 4)

y = (x − 4)(x − 4) + 1

Multiply the binomials.

(x − 4)(x − 4)

x² − 4x − 4x + 16

Distribute the a-value.

a = 1

y = 1(x² − 4x − 4x + 16) + 1

y = x² − 4x − 4x + 16 + 1

Combine like terms.

−4x − 4x = −8x

16 + 1 = 17

y = x² − 8x + 17

Answer: y = x² − 8x + 17

1
Write in standard form. y = (x − 2)² + 5
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 2)²

(x − 2)(x − 2)

y = (x − 2)(x − 2) + 5

Multiply the binomials.

(x − 2)(x − 2)

x² − 2x − 2x + 4

Distribute the a-value.

a = 1

y = 1(x² − 2x − 2x + 4) + 5

y = x² − 2x − 2x + 4 + 5

Combine like terms.

−2x − 2x = −4x

4 + 5 = 9

y = x² − 4x + 9

Answer: y = x² − 4x + 9

2
Write in standard form. y = (x + 3)² − 4
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 3)²

(x + 3)(x + 3)

y = (x + 3)(x + 3) − 4

Multiply the binomials.

(x + 3)(x + 3)

x² + 3x + 3x + 9

Distribute the a-value.

a = 1

y = 1(x² + 3x + 3x + 9) − 4

y = x² + 3x + 3x + 9 − 4

Combine like terms.

3x + 3x = 6x

9 − 4 = 5

y = x² + 6x + 5

Answer: y = x² + 6x + 5

3
Write in standard form. y = (x − 1)² − 6
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 1)²

(x − 1)(x − 1)

y = (x − 1)(x − 1) − 6

Multiply the binomials.

(x − 1)(x − 1)

x² − x − x + 1

Distribute the a-value.

a = 1

y = 1(x² − x − x + 1) − 6

y = x² − x − x + 1 − 6

Combine like terms.

−x − x = −2x

1 − 6 = −5

y = x² − 2x − 5

Answer: y = x² − 2x − 5

4
Write in standard form. y = (x + 6)² + 2
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 6)²

(x + 6)(x + 6)

y = (x + 6)(x + 6) + 2

Multiply the binomials.

(x + 6)(x + 6)

x² + 6x + 6x + 36

Distribute the a-value.

a = 1

y = 1(x² + 6x + 6x + 36) + 2

y = x² + 6x + 6x + 36 + 2

Combine like terms.

6x + 6x = 12x

36 + 2 = 38

y = x² + 12x + 38

Answer: y = x² + 12x + 38

5
Write in standard form. y = (x − 5)²
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 5)²

(x − 5)(x − 5)

y = (x − 5)(x − 5)

Multiply the binomials.

(x − 5)(x − 5)

x² − 5x − 5x + 25

Distribute the a-value.

a = 1

y = 1(x² − 5x − 5x + 25)

y = x² − 5x − 5x + 25

Combine like terms.

−5x − 5x = −10x

y = x² − 10x + 25

Answer: y = x² − 10x + 25

Medium 1

Root → Standard, a = integer

Expand the parenthesis. Multiply the binomials. Combine like terms inside the parentheses. Distribute the a-value.

Example
Write in standard form. y = 2(x − 4)(x + 3)

Expand the parenthesis.

y = a(x − r)(x − s)

y = 2(x − 4)(x + 3)

Multiply the binomials.

(x − 4)(x + 3)

x² + 3x − 4x − 12

Combine like terms inside the parentheses.

y = 2(x² + 3x − 4x − 12)

3x − 4x = −x

y = 2(x² − x − 12)

Distribute the a-value.

a = 2

y = 2x² − 2x − 24

Answer: y = 2x² − 2x − 24

1
Write in standard form. y = 3(x + 2)(x − 5)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 3(x + 2)(x − 5)

Multiply the binomials.

(x + 2)(x − 5)

x² − 5x + 2x − 10

Combine like terms inside the parentheses.

y = 3(x² − 5x + 2x − 10)

−5x + 2x = −3x

y = 3(x² − 3x − 10)

Distribute the a-value.

a = 3

y = 3x² − 9x − 30

Answer: y = 3x² − 9x − 30

2
Write in standard form. y = −2(x − 3)(x + 1)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = −2(x − 3)(x + 1)

Multiply the binomials.

(x − 3)(x + 1)

x² + x − 3x − 3

Combine like terms inside the parentheses.

y = −2(x² + x − 3x − 3)

x − 3x = −2x

y = −2(x² − 2x − 3)

Distribute the a-value.

a = −2

y = −2x² + 4x + 6

Answer: y = −2x² + 4x + 6

3
Write in standard form. y = 4(x + 1)(x + 2)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 4(x + 1)(x + 2)

Multiply the binomials.

(x + 1)(x + 2)

x² + 2x + x + 2

Combine like terms inside the parentheses.

y = 4(x² + 2x + x + 2)

2x + x = 3x

y = 4(x² + 3x + 2)

Distribute the a-value.

a = 4

y = 4x² + 12x + 8

Answer: y = 4x² + 12x + 8

4
Write in standard form. y = −3(x − 2)(x − 6)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = −3(x − 2)(x − 6)

Multiply the binomials.

(x − 2)(x − 6)

x² − 6x − 2x + 12

Combine like terms inside the parentheses.

y = −3(x² − 6x − 2x + 12)

−6x − 2x = −8x

y = −3(x² − 8x + 12)

Distribute the a-value.

a = −3

y = −3x² + 24x − 36

Answer: y = −3x² + 24x − 36

5
Write in standard form. y = 5x(x − 2)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 5x(x − 2)

Multiply the binomials.

x(x − 2)

x² − 2x

Distribute the a-value.

a = 5

y = 5(x² − 2x)

y = 5x² − 10x

Combine like terms.

y = 5x² − 10x

Answer: y = 5x² − 10x

Medium 2

Vertex → Standard, a = integer

Expand the parenthesis. Multiply the binomials. Combine like terms inside the parentheses. Distribute the a-value. Combine the constant.

Example
Write in standard form. y = 2(x − 3)² + 1

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 3)²

(x − 3)(x − 3)

y = 2(x − 3)(x − 3) + 1

Multiply the binomials.

(x − 3)(x − 3)

x² − 3x − 3x + 9

Combine like terms inside the parentheses.

y = 2(x² − 3x − 3x + 9) + 1

−3x − 3x = −6x

y = 2(x² − 6x + 9) + 1

Distribute the a-value.

a = 2

y = 2x² − 12x + 18 + 1

Combine like terms.

18 + 1 = 19

y = 2x² − 12x + 19

Answer: y = 2x² − 12x + 19

1
Write in standard form. y = 3(x − 1)² − 4
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 1)²

(x − 1)(x − 1)

y = 3(x − 1)(x − 1) − 4

Multiply the binomials.

(x − 1)(x − 1)

x² − x − x + 1

Combine like terms inside the parentheses.

y = 3(x² − x − x + 1) − 4

−x − x = −2x

y = 3(x² − 2x + 1) − 4

Distribute the a-value.

a = 3

y = 3x² − 6x + 3 − 4

Combine like terms.

3 − 4 = −1

y = 3x² − 6x − 1

Answer: y = 3x² − 6x − 1

2
Write in standard form. y = −2(x + 4)² + 5
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 4)²

(x + 4)(x + 4)

y = −2(x + 4)(x + 4) + 5

Multiply the binomials.

(x + 4)(x + 4)

x² + 4x + 4x + 16

Combine like terms inside the parentheses.

y = −2(x² + 4x + 4x + 16) + 5

4x + 4x = 8x

y = −2(x² + 8x + 16) + 5

Distribute the a-value.

a = −2

y = −2x² − 16x − 32 + 5

Combine like terms.

−32 + 5 = −27

y = −2x² − 16x − 27

Answer: y = −2x² − 16x − 27

3
Write in standard form. y = 4(x − 2)² + 3
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 2)²

(x − 2)(x − 2)

y = 4(x − 2)(x − 2) + 3

Multiply the binomials.

(x − 2)(x − 2)

x² − 2x − 2x + 4

Combine like terms inside the parentheses.

y = 4(x² − 2x − 2x + 4) + 3

−2x − 2x = −4x

y = 4(x² − 4x + 4) + 3

Distribute the a-value.

a = 4

y = 4x² − 16x + 16 + 3

Combine like terms.

16 + 3 = 19

y = 4x² − 16x + 19

Answer: y = 4x² − 16x + 19

4
Write in standard form. y = −(x − 5)² + 2
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 5)²

(x − 5)(x − 5)

y = −(x − 5)(x − 5) + 2

Multiply the binomials.

(x − 5)(x − 5)

x² − 5x − 5x + 25

Combine like terms inside the parentheses.

y = −1(x² − 5x − 5x + 25) + 2

−5x − 5x = −10x

y = −1(x² − 10x + 25) + 2

Distribute the a-value.

a = −1

y = −x² + 10x − 25 + 2

Combine like terms.

−25 + 2 = −23

y = −x² + 10x − 23

Answer: y = −x² + 10x − 23

5
Write in standard form. y = 2(x + 1)² − 6
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 1)²

(x + 1)(x + 1)

y = 2(x + 1)(x + 1) − 6

Multiply the binomials.

(x + 1)(x + 1)

x² + x + x + 1

Combine like terms inside the parentheses.

y = 2(x² + x + x + 1) − 6

x + x = 2x

y = 2(x² + 2x + 1) − 6

Distribute the a-value.

a = 2

y = 2x² + 4x + 2 − 6

Combine like terms.

2 − 6 = −4

y = 2x² + 4x − 4

Answer: y = 2x² + 4x − 4

Hard 1

Root → Standard, a = fraction

Expand the parenthesis. Multiply the binomials. Combine like terms inside the parentheses. Distribute the a-value.

Example
Write in standard form. y = 12(x − 4)(x + 2)

Expand the parenthesis.

y = a(x − r)(x − s)

y = 12(x − 4)(x + 2)

Multiply the binomials.

(x − 4)(x + 2)

x² + 2x − 4x − 8

Combine like terms inside the parentheses.

y = 12(x² + 2x − 4x − 8)

2x − 4x = −2x

y = 12(x² − 2x − 8)

Distribute the a-value.

a = 12

y = 12x² − 22x − 82

y = 12x² − x − 4

Answer: y = 12x² − x − 4

1
Write in standard form. y = 13(x − 3)(x + 6)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 13(x − 3)(x + 6)

Multiply the binomials.

(x − 3)(x + 6)

x² + 6x − 3x − 18

Combine like terms inside the parentheses.

y = 13(x² + 6x − 3x − 18)

6x − 3x = 3x

y = 13(x² + 3x − 18)

Distribute the a-value.

a = 13

y = 13x² + 33x − 183

y = 13x² + x − 6

Answer: y = 13x² + x − 6

2
Write in standard form. y = 32(x − 1)(x − 5)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 32(x − 1)(x − 5)

Multiply the binomials.

(x − 1)(x − 5)

x² − 5x − x + 5

Combine like terms inside the parentheses.

y = 32(x² − 5x − x + 5)

−5x − x = −6x

y = 32(x² − 6x + 5)

Distribute the a-value.

a = 32

y = 32x² − 182x + 152

y = 32x² − 9x + 152

Answer: y = 32x² − 9x + 152

3
Write in standard form. y = −12(x + 2)(x − 4)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = −12(x + 2)(x − 4)

Multiply the binomials.

(x + 2)(x − 4)

x² − 4x + 2x − 8

Combine like terms inside the parentheses.

y = −12(x² − 4x + 2x − 8)

−4x + 2x = −2x

y = −12(x² − 2x − 8)

Distribute the a-value.

a = −12

y = −12x² + 22x + 82

y = −12x² + x + 4

Answer: y = −12x² + x + 4

4
Write in standard form. y = 23(x − 3)(x + 3)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = 23(x − 3)(x + 3)

Multiply the binomials.

(x − 3)(x + 3)

x² + 3x − 3x − 9

Combine like terms inside the parentheses.

y = 23(x² + 3x − 3x − 9)

3x − 3x = 0

y = 23(x² − 9)

Distribute the a-value.

a = 23

y = 23x² − 183

y = 23x² − 6

Answer: y = 23x² − 6

5
Write in standard form. y = −34(x − 2)(x − 6)
Show Answer

Expand the parenthesis.

y = a(x − r)(x − s)

y = −34(x − 2)(x − 6)

Multiply the binomials.

(x − 2)(x − 6)

x² − 6x − 2x + 12

Combine like terms inside the parentheses.

y = −34(x² − 6x − 2x + 12)

−6x − 2x = −8x

y = −34(x² − 8x + 12)

Distribute the a-value.

a = −34

y = −34x² + 244x − 364

y = −34x² + 6x − 9

Answer: y = −34x² + 6x − 9

Hard 2

Vertex → Standard, a = fraction

Expand the parenthesis. Multiply the binomials. Combine like terms inside the parentheses. Distribute the a-value. Combine the constant.

Example
Write in standard form. y = 12(x − 4)² + 3

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 4)²

(x − 4)(x − 4)

y = 12(x − 4)(x − 4) + 3

Multiply the binomials.

(x − 4)(x − 4)

x² − 4x − 4x + 16

Combine like terms inside the parentheses.

y = 12(x² − 4x − 4x + 16) + 3

−4x − 4x = −8x

y = 12(x² − 8x + 16) + 3

Distribute the a-value.

a = 12

y = 12x² − 82x + 162 + 3

y = 12x² − 4x + 8 + 3

Combine like terms.

8 + 3 = 11

y = 12x² − 4x + 11

Answer: y = 12x² − 4x + 11

1
Write in standard form. y = 13(x − 3)² − 1
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 3)²

(x − 3)(x − 3)

y = 13(x − 3)(x − 3) − 1

Multiply the binomials.

(x − 3)(x − 3)

x² − 3x − 3x + 9

Combine like terms inside the parentheses.

y = 13(x² − 3x − 3x + 9) − 1

−3x − 3x = −6x

y = 13(x² − 6x + 9) − 1

Distribute the a-value.

a = 13

y = 13x² − 63x + 93 − 1

y = 13x² − 2x + 3 − 1

Combine like terms.

3 − 1 = 2

y = 13x² − 2x + 2

Answer: y = 13x² − 2x + 2

2
Write in standard form. y = 32(x + 2)² − 4
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 2)²

(x + 2)(x + 2)

y = 32(x + 2)(x + 2) − 4

Multiply the binomials.

(x + 2)(x + 2)

x² + 2x + 2x + 4

Combine like terms inside the parentheses.

y = 32(x² + 2x + 2x + 4) − 4

2x + 2x = 4x

y = 32(x² + 4x + 4) − 4

Distribute the a-value.

a = 32

y = 32x² + 122x + 122 − 4

y = 32x² + 6x + 6 − 4

Combine like terms.

6 − 4 = 2

y = 32x² + 6x + 2

Answer: y = 32x² + 6x + 2

3
Write in standard form. y = −12(x − 2)² + 5
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 2)²

(x − 2)(x − 2)

y = −12(x − 2)(x − 2) + 5

Multiply the binomials.

(x − 2)(x − 2)

x² − 2x − 2x + 4

Combine like terms inside the parentheses.

y = −12(x² − 2x − 2x + 4) + 5

−2x − 2x = −4x

y = −12(x² − 4x + 4) + 5

Distribute the a-value.

a = −12

y = −12x² + 42x − 42 + 5

y = −12x² + 2x − 2 + 5

Combine like terms.

−2 + 5 = 3

y = −12x² + 2x + 3

Answer: y = −12x² + 2x + 3

4
Write in standard form. y = 23(x + 3)² + 1
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x + 3)²

(x + 3)(x + 3)

y = 23(x + 3)(x + 3) + 1

Multiply the binomials.

(x + 3)(x + 3)

x² + 3x + 3x + 9

Combine like terms inside the parentheses.

y = 23(x² + 3x + 3x + 9) + 1

3x + 3x = 6x

y = 23(x² + 6x + 9) + 1

Distribute the a-value.

a = 23

y = 23x² + 123x + 183 + 1

y = 23x² + 4x + 6 + 1

Combine like terms.

6 + 1 = 7

y = 23x² + 4x + 7

Answer: y = 23x² + 4x + 7

5
Write in standard form. y = −14(x − 6)² + 2
Show Answer

Expand the parenthesis.

(x − h)² = (x − h)(x − h)

(x − 6)²

(x − 6)(x − 6)

y = −14(x − 6)(x − 6) + 2

Multiply the binomials.

(x − 6)(x − 6)

x² − 6x − 6x + 36

Combine like terms inside the parentheses.

y = −14(x² − 6x − 6x + 36) + 2

−6x − 6x = −12x

y = −14(x² − 12x + 36) + 2

Distribute the a-value.

a = −14

y = −14x² + 124x − 364 + 2

y = −14x² + 3x − 9 + 2

Combine like terms.

−9 + 2 = −7

y = −14x² + 3x − 7

Answer: y = −14x² + 3x − 7

Need help converting to standard form?

Book a Session with Amy