Find cos ⍬ for a ⍬ whose terminal side passes through the point (20,15)?

What is the exact area of a circle with a diameter of 50 centimeters? a.87.9 square centimeters b.379.9 square centimeters c.1962.5 square centimeters d.4923.5 square centimeters

Use set buikder notation to represent the following set: {, -2, -1, 0}

For f(x)=2x+3 and g(x)=x^2- 8 find (f+g) (x)