Twice the sum of -4 and a number is the same as the number decreased by 7/2

Answer this 30 points and brainliest!

Asailor is looking at a kite. if he is looking at the kite at an angle of elevation of 36and the distance from the boat to the point where the kite is directly overhead is 40 feet, how high is the kite?

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