If F = x^2y/z^3 and x = 3, y = 5 and z = -2, then F = (picture incoluded)

The triangles are similar. what is the value of x? enter your answer in the box. x = two right triangles. the larger right triangle is labeled x on the longer leg, 12 on the shorter leg and 20 on the hypotenuse. the smaller triangle is labeled 4 on the longer leg, 3 on the shorter leg, and 5 on the hypotenuse.

What is the equation of the graph that represents f(x)=x^4 stretched vertically by 2 and shifted up 3 spaces

Having a hard time understanding this question (see attachment).