Question

Engineers are analyzing the performance of windshield wiper blades. At the end of one swipe, the tip of a blade is at (−5, 7) when represented graphically. What is the sine value of this function?

a. negative 7 square root 74 divided by 74
b. 7 times square root of 74 over 74
c. square root 74
d. negative 5 times square root of 74 over 74

Answer 1

Wrong. The correct answer is POSITIVE 7 square root of 74 over 74

Answer 2

The sin value = sin(arctan(7/-5)) = (-7/5)/sqrt(1 + (-7/5)^2) = (-7/5)/sqrt(1 + 49/25) = (-7/5)/(1/5)sqrt(25 + 49) = -7/sqrt(74) = -7sqrt(74) / 74

Therefore, the sine value of the function is negative 7 square root 74 divided by 74