Sides in Quadrilaterals | Math Coach Amy

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What to Remember

Parallelogram sides

Opposite sides of a parallelogram match.

An adjacent side can be a different length. Do not copy the adjacent side when the question asks for the opposite side.

Rhombus and square

All sides of a rhombus or a square match.

The perimeter is 4 times one side.

Isosceles trapezoid

Only the legs of an isosceles trapezoid match, not the bases.

The two bases are the parallel sides, and they have different lengths.

Level 1

Easy

Opposite sides of a parallelogram are equal.

Example

A parallelogram has a top side of 9 cm. The bottom is the opposite side. How long is the bottom?

Opposite sides of a parallelogram are equal.

The bottom is 9 cm.

Answer: 9 cm

A parallelogram has a top side of 6 cm. The bottom is the opposite side. How long is the bottom?

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Opposite sides of a parallelogram are equal.

The bottom is 6 cm.

Answer: 6 cm

A parallelogram has a top side of 12 cm. The bottom is the opposite side. How long is the bottom?

Show Answer

Opposite sides of a parallelogram are equal.

The bottom is 12 cm.

Answer: 12 cm

A parallelogram has a left side of 5 cm. The right side is the opposite side. How long is the right side?

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Opposite sides of a parallelogram are equal.

The right side is 5 cm.

Answer: 5 cm

A parallelogram has a left side of 8 in. The right side is the opposite side. How long is the right side?

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Opposite sides of a parallelogram are equal.

The right side is 8 in.

Answer: 8 in

A parallelogram has a top side of 4 ft. The bottom is the opposite side. How long is the bottom?

Show Answer

Opposite sides of a parallelogram are equal.

The bottom is 4 ft.

Answer: 4 ft

A parallelogram has a top side of 15 cm. The bottom is the opposite side. How long is the bottom?

Show Answer

Opposite sides of a parallelogram are equal.

The bottom is 15 cm.

Answer: 15 cm

A parallelogram has a bottom side of 11 cm. The top is the opposite side. How long is the top?

Show Answer

Opposite sides of a parallelogram are equal.

The top is 11 cm.

Answer: 11 cm

A parallelogram has a right side of 7 cm. The left side is the opposite side. How long is the left side?

Show Answer

Opposite sides of a parallelogram are equal.

The left side is 7 cm.

Answer: 7 cm

A parallelogram has a top side of 14 in. The bottom is the opposite side. How long is the bottom?

Show Answer

Opposite sides of a parallelogram are equal.

The bottom is 14 in.

Answer: 14 in

A parallelogram has a left side of 3 ft. The right side is the opposite side. How long is the right side?

Show Answer

Opposite sides of a parallelogram are equal.

The right side is 3 ft.

Answer: 3 ft

Level 2

Medium

Every side of a rhombus or a square is the same length.

Example

A rhombus has all sides equal. One side is 5 cm. Find the perimeter.

All sides of a rhombus are equal.

Each side is 5 cm.

5 + 5 + 5 + 5 = 20

4 × 5 = 20

Answer: 20 cm

A square has all sides equal. One side is 3 cm. Find the perimeter.

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All sides of a square are equal.

Each side is 3 cm.

3 + 3 + 3 + 3 = 12

4 × 3 = 12

Answer: 12 cm

A rhombus has all sides equal. One side is 4 cm. Find the perimeter.

Show Answer

All sides of a rhombus are equal.

Each side is 4 cm.

4 + 4 + 4 + 4 = 16

4 × 4 = 16

Answer: 16 cm

A square has all sides equal. One side is 6 in. Find the perimeter.

Show Answer

All sides of a square are equal.

Each side is 6 in.

6 + 6 + 6 + 6 = 24

4 × 6 = 24

Answer: 24 in

A rhombus has all sides equal. One side is 7 cm. Find the perimeter.

Show Answer

All sides of a rhombus are equal.

Each side is 7 cm.

7 + 7 + 7 + 7 = 28

4 × 7 = 28

Answer: 28 cm

A square has all sides equal. One side is 8 cm. Find the perimeter.

Show Answer

All sides of a square are equal.

Each side is 8 cm.

8 + 8 + 8 + 8 = 32

4 × 8 = 32

Answer: 32 cm

A rhombus has all sides equal. One side is 9 in. Find the perimeter.

Show Answer

All sides of a rhombus are equal.

Each side is 9 in.

9 + 9 + 9 + 9 = 36

4 × 9 = 36

Answer: 36 in

A square has all sides equal. One side is 10 ft. Find the perimeter.

Show Answer

All sides of a square are equal.

Each side is 10 ft.

10 + 10 + 10 + 10 = 40

4 × 10 = 40

Answer: 40 ft

A rhombus has all sides equal. One side is 12 cm. Find the perimeter.

Show Answer

All sides of a rhombus are equal.

Each side is 12 cm.

12 + 12 + 12 + 12 = 48

4 × 12 = 48

Answer: 48 cm

A square has all sides equal. One side is 15 cm. Find the perimeter.

Show Answer

All sides of a square are equal.

Each side is 15 cm.

15 + 15 + 15 + 15 = 60

4 × 15 = 60

Answer: 60 cm

A rhombus has all sides equal. One side is 11 cm. Find the perimeter.

Show Answer

All sides of a rhombus are equal.

Each side is 11 cm.

11 + 11 + 11 + 11 = 44

4 × 11 = 44

Answer: 44 cm

Level 3

Hard

Match the sides that are supposed to match. Do not match the others.

Example

An isosceles trapezoid has equal legs. One leg is 7 cm. The bases are 4 cm and 12 cm. How long is the other leg?

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 7 cm.

Answer: 7 cm

An isosceles trapezoid has equal legs. One leg is 5 cm. The bases are 3 cm and 9 cm. How long is the other leg?

Show Answer

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 5 cm.

Answer: 5 cm

An isosceles trapezoid has equal legs. One leg is 6 cm. The bases are 8 cm and 14 cm. How long is the other leg?

Show Answer

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 6 cm.

Answer: 6 cm

An isosceles trapezoid has equal legs. One leg is 9 in. The bases are 5 in and 11 in. How long is the other leg?

Show Answer

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 9 in.

Answer: 9 in

An isosceles trapezoid has equal legs. One leg is 4 ft. The bases are 6 ft and 10 ft. How long is the other leg?

Show Answer

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 4 ft.

Answer: 4 ft

An isosceles trapezoid has equal legs. One leg is 8 cm. The bases are 2 cm and 15 cm. How long is the other leg?

Show Answer

The legs of an isosceles trapezoid are equal.

The two bases are different lengths. Do not replace the leg with a base.

The other leg is 8 cm.

Answer: 8 cm

A parallelogram has a side of 8 cm. The adjacent side is 5 cm. How long is the side opposite the 8 cm side?

Show Answer

Opposite sides of a parallelogram are equal.

An adjacent side does not have to match the given side.

The side opposite the 8 cm side is 8 cm.

Answer: 8 cm

A parallelogram has a side of 10 cm. The adjacent side is 3 cm. How long is the side opposite the 10 cm side?

Show Answer

Opposite sides of a parallelogram are equal.

An adjacent side does not have to match the given side.

The side opposite the 10 cm side is 10 cm.

Answer: 10 cm

A parallelogram has a side of 6 in. The adjacent side is 4 in. How long is the side opposite the 6 in side?

Show Answer

Opposite sides of a parallelogram are equal.

An adjacent side does not have to match the given side.

The side opposite the 6 in side is 6 in.

Answer: 6 in

A parallelogram has a side of 12 cm. The adjacent side is 7 cm. How long is the side opposite the 7 cm side?

Show Answer

Opposite sides of a parallelogram are equal.

An adjacent side does not have to match the given side.

The side opposite the 7 cm side is 7 cm.

Answer: 7 cm

A parallelogram has a side of 9 ft. The adjacent side is 2 ft. How long is the side opposite the 9 ft side?

Show Answer

Opposite sides of a parallelogram are equal.

An adjacent side does not have to match the given side.

The side opposite the 9 ft side is 9 ft.

Answer: 9 ft

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