HELP! This isn’t math but please I would really appreciate answers

Consider the function f(x)=-5x+3 what is f(-2)

Asquare has a side that measures 11 units. what is the area of a circle with a circumference that equals the perimeter of the square? use 3.14 for π, and round your answer to the nearest hundredth. 1519.76 units2 379.94 units2 616.56 units2 154.14 units2

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.