Understanding Area Calculations in Geometry

The video tutorial explains how to find the approximate area of a shaded region in a circle by subtracting the area of an unshaded triangle from the circle's total area. The instructor introduces a strategy, applies formulas for circle and triangle areas, and performs step-by-step calculations to arrive at the final result. The tutorial concludes with selecting the best approximate answer from given choices.

What is the first step in solving the problem of finding the shaded area?

• Subtract the area of the circle from the triangle.

• Find the area of the circle.

• Multiply the areas of the circle and triangle.

• Find the area of the triangle.

Tags

CCSS.1.G.A.2

What shape is subtracted from the circle to find the shaded area?

• Rectangle

• Pentagon

• Square

• Triangle

Tags

CCSS.7.G.B.4

What is the formula for the area of a circle?

• r squared

• pi r squared

• pi d

• 2 pi r

Tags

CCSS.6.G.A.1

How do you calculate the area of a triangle?

• Base minus height

• Base plus height

• One half base times height

• Base times height

Tags

CCSS.7.G.B.4

What is the radius of the circle if the diameter is 14?

• 14

• 28

• 21

• 7

What is the base of the triangle in the problem?

• 7

• 14

• 21

• 28

What is the height of the triangle in relation to the circle?

• Circumference

• Area

• Radius

• Diameter

What is the result of subtracting the area of the triangle from the circle?

• 49 pi

• 49 pi minus 49

• 49

• 104.9

Tags

CCSS.7.G.B.4

What is the approximate value of the shaded area?

• 105

• 104.9

• 49 pi

• 49

Which choice represents the best approximation for the shaded area?

• D

• C

• B

• A