Geometry 2D

The perimeter around a circle is the ____

• Perimeter

• Radius

• Diameter

• Circumference

Angles that equal 180 degrees when added are ____

• Congruent

• Supplementary

• Similar Figures

• Complementary

The width of a circle when measured through its center is the ____

• Radius

• Diameter

• Circumference

• Area

____ is when two figures are the same shape and have proportional sides with congruent angles.

• Composite Figure

• Scale Factor

• Congruent

• Similar Figures

What is the diameter?

• 8

• 16

• 10

• 4

What is the radius?

• 18

• 72

• 38

• 14

What is the circumference?

• 36

• 18π

• 108π

• 36π

Diameter 13.5 in
Find the circumference of the circle.

• 84.79 in

• 42.39 in

• 21.195 in

• 572.265 in 

Other than the formula C=πd what is another formula for circumference of a circle?

• C=2π

• C=2πr

• C=πr²

• C=πd²

what is the circumference of this circle ?

• 3.14 cm 

• 37.68 cm

• 24 cm

• 68.4 cm