This handy Math in Focus Grade 3 Workbook Answer Key Chapter 17 Practice 3 Perpendicular Lines provides detailed solutions for the textbook questions.

## Math in Focus Grade 3 Chapter 17 Practice 3 Answer Key Perpendicular Lines

**Guess if the lines are perpendicular. Use a ruler to check your guess.**

Question 1.

Answer:

The lines are perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the wx and yz is 90 degrees.

Question 2.

Answer:

The lines are not perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the pq and rs is greater then 90 degrees.

Question 3.

Answer:

The lines are not perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the ab and cd is greater then 90 degrees.

Question 4.

Answer:

The lines are perpendicular and the angle between the ij and kl is 90 degrees

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular,

Question 5.

Answer:

The lines are not perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the ab and cd is greater then 90 degrees.

Question 6.

Answer:

The lines are perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the pq and rs is 90 degrees.

**Check (✓) the box if the lines are perpendicular.**

Answer:

Explanation:

From the above figures we can come to conclusion that figures 1, 4 and 6 are parallel lines and

figures 2,3 and 5 are not parallel lines.

**Use a ruler to check for perpendicular lines. Use a colored pencil to trace a pair of perpendicular lines in each figure.**

Question 7.

Answer:

The lines are perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the wx and yz is 90 degrees.

Question 8.

Answer:

The lines are perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the pq and rs is 90 degrees.

Question 9.

Answer:

The lines are perpendicular.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the pq and rs is 90 degrees.

Question 10.

Answer:

The lines are perpendicular

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the angle between the ij and kl is 90 degrees.

**Circle the letters that have perpendicular line segments.**

Question 11.

Answer:

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

So, the letters T,L,E,H,F are perpendicular line segmests.

**Name all the pairs of perpendicular line segments in each figure.**

**Example**

Segments AB and BC

Question 12.

Answer:

The pairs of perpendicular line segments

Segments RQ and QP

Segments OP and ON

Segments MN and MR

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

The colors of lines indicate different pairs of line segments.

Question 13.

Answer:

The pairs of perpendicular line segments are:

Segments AB and AG

Segments AB and BC

Segments FE and DE

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

The colors of lines indicate different pairs of line segments.

Question 14.

Answer:

The pairs of perpendicular line segments are:

Segments MT and TS

Segments RS and TS

Segments OP and PQ

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

The colors of lines indicate different pairs of line segments.

**Identify and name a pair of perpendicular line segments on each object.**

Question 15.

Answer:

A pair of perpendicular line segments on each object are,

AF and FE

BE and ED

CD and DE are a pair of perpendicular line segments.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

Question 16.

Answer:

A pair of perpendicular line segments on Encyclopedia are,

RS and RX

SV and VX

SV and VU are a pair of perpendicular line segments.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.

**Carry out this activity.**

Question 17.

Think of two objects that have perpendicular line segments. Use the Internet to find pictures of these objects. Print and paste them below. Use a colored pencil to trace a pair of perpendicular line segments on each object.

Answer:

A pair of perpendicular line segments on objects are,

AB and ET

CE and ET

LM and mj

LN and NK

are a pair of perpendicular line segments.

Explanation:

If the intersection between the two line segment is at a right angle, then the two lines are perpendicular.