Question

Part A What is the area of the blue shaded figure ( π=3.14)? Justify your answer using equations, models, and/or words to explain your mathematical reasoning. Part B What is the perimeter of the blue shaded figure (π=3.14)? Justify your answer using equations, models, and/or words to explain your mathematical reasoning.

Answer 1

1372 cm²

Explanation:

First, find the area of the rectangle:

A = lw

A = 40(50)

A = 2000 cm²

Next, find the area of the semicircle:

A =(
`\pi`r²) / 2

A = (3.14)(20)²

A = 1256/2

A = 628 cm²

Then, subtract the semicircle area from the rectangle's area:

2000 - 628

= 1372 cm²

Answer 2

1372cm²

Explanation:

If this were a complete rectangle, it would be 50x40=2000cm². So we need to take that number and subtract the half-circle. A=
`\pi`r² A=3.14*20*20=1256

1256*1/2 = 628

2000-628=1372cm²