A square surrounds a circle with a radius r. Each expression represents the area of part of this figure. Describe the shape or region each area represents.

Question

a. 4r2 − πr2

b. 4r2 − (πr2)/2

Answer 1

a. 4r^2 is the entire square, subtract pir^2 and that leaves the 4 shaded darker areas outside the circle

b this is half the square plus 2 of the shaded areas in the other half of the square