Adding Angles at the Pizza Party

Put pizza-slice angles together and find the missing slices.

Put the slices together

Each pizza slice makes an angle at the center of the pizza. Add the parts to find the whole angle.

Ravi puts two slices side by side. What is the angle of the two slices together?

The two slices make an angle of °.

A cut splits angle ABC into two slices. What is the measure of angle ABC?

Angle ABC = °

Lena puts three slices side by side with no gaps. The slices measure 40°, 40°, and 25°. What angle do all three slices make together?

A. 80°B. 65°C. 105°D. 115°

Each friend puts two slices side by side. Match each pair of slices to the angle they make together.

Find the missing slice

Use the whole angle and the part you know. Find the angle marked x.

Two slices fill a right angle of 90°. One slice is 35°.

x = °

Half of a pizza makes a straight angle of 180°. Marco cuts the half into two slices. One slice is 115°.

x = °

Priya's big piece of pizza makes a 150° angle. She cuts it into two slices. One slice is 65°.

x = °

Which equation can you use to find x?

A. x = 130 + 50B. x = 180 − 130C. x = 130 − 50D. x = 50 + 50

Use the protractor to read the whole angle. Then use the 60° part to find x.

Whole angle = °
x = °

Pizza angle puzzles

Add or subtract angle measures to solve each puzzle.

10.

Each pair of slices sits side by side. Sort the pairs: do they make a right angle (90°) or not?

11.

A whole pizza makes a full turn of 360° around its center. Mia takes a 90° slice, Theo takes a 120° slice, and Ava takes a 100° slice. What angle of pizza is left?

12.

Noah puts a 50° slice next to a 40° slice. He says the two slices make a 90° angle. Sam says they make a 10° angle because you subtract. Who is right? Explain.