IXL | Side lengths and angle measures of similar triangles

If these two shapes are similar, what is the measure of the missing length a?

4 km

1 km

2 km

a = kilometers

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If these two shapes are similar, what is the measure of the missing length b?

12 cm

4 cm

3 cm

b = centimeters

The corresponding sides of similar shapes are proportional.

12 cm

4 cm

3 cm

The triangles' longer sides have a ratio of

, which is

.

The triangles' shorter sides have a ratio of

.

Write a proportion:

Multiply both sides by b and solve:

The missing length is 1 centimeter.

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