Help on Radian Measure of Angles Question. Find the area covered by the wiper.?

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A car's rear windshield wiper rotates 135 degrees.
The wiper mechanism has a total length of 23 inches
and wipes the windshield over a distance of 14 inches.
Find the area covered by the wiper.
Convert 135° to radians:
θ
= 135 * (π/180) radians
= 3π/4 radians
Arc radius = 14 inches
Area of a sector of a circle = (1/2) * r^2 * θ
A_23 = (1/2) * (23^2) * (3pi/4) = 15625pi/72 ≈ 217pi in^2
A_11 = (1/2)(11^2)(25pi/36) = 3025pi/72 ≈ 42pi in^2
A = 217pi - 42pi = 175pi in^2...Show more

Convert 135° to radians:
θ
= 135 * (π/180) radians
= 3π/4 radians
Area of a sector of a circle = (1/2) * r^2 * θ
A_23 = (1/2) * (23^2) * (3π/4) = 1587 π/8
A_9 = (1/2) * (9^2) * (3π/4) = 243 π/8
Area covered by the wiper
= 1344 π/8
≈ 527.7875658... in^2...Show more