Similarity of Shapes

Similarity

Similar Shapes

Similar Shapes

Have equal angles and proportional sides

Equal Angles

Triangles have interior angles that add up to 180 degress

​Remember

Multiple Choice

If triangles ABC and PQR are similar, what is the measure of angle C?

• 70

• 75

• 35

• Not able to be determined

Divide the corresponding (matching) sides

​What is the rule for the ray?

Proportional Sides

Fill in the Blanks

What is the scale factor?

All the sides use the same rule

​Similar if...

Similarity

Multiple Choice

Are the triangles similar?

• Similar

• Not Similar

Multiply or divide by the scale factor to find the missing length

​Find the missing side

Divide the known corresponding lengths to find the scale factor
Tips: make sure you are comparing matching sides
Double check if you should be multiplying or dividing

​First, identify the rule

Finding Missing Side Lengths

Fill in the Blanks

If the two figures are similar, what is the value of x?