Lesson 1 Similar Triangles

The figures are similar. Find the scale factor of the smaller figure to the larger figure.

• 2:5
• 5:3
• 3:5
• 2:3

If ABCDE ∼ GHJDF, then∠B is congruent to _______

• ∠H
• ∠D
• ∠F
• ∠J

What is the measure of x?

• 12
• 15
• 6
• 9

If two figures are similar their angles are______.

• proportional
• congruent
• supplementary
• complementary

Find missing side

• 5
• 7
• 9
• 11

If the scale factor is 4, what is the measurement of x?

• 20 m
• 24 m
• 16 m
• 4 m

What is the scale factor from triangle ABC to triangle DEF?

• 1/2
• 7/3
• 2/1
• 10/3

The two right triangles below are similar. What is x, the missing side length in triangle DEF? 

• 3.75
• 9.75
• 10
• 12

Find side length X.

• 22.5
• 10
• 9
• 7.5

Which triangles are similar to triangle A?

• B
• C
• Both
• None