One half minus seven eighths

Given f(x)=2x^2-8x+6 and g(x)=3x-1 find f(x) +g(x) a. 2x^2+5x+5 b.2x^2-11x+7 c. 2x^2-5x+5 d.2x^2-5x-5

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.