Is 8/20 and 20/80 proportional or not proportional

Question: what is the value of x 4x-2= (-7) +5x. it would be greatly appreciated if someone could actually explain to me step by step

The lengths of two sides of a right triangle are given. find the length of the third side. round to the nearest tenth if necessary. a) y = 12/5x + 39/5 b) y = 5/12x + 5/39 c) y = 12/5x - 39/5 d) y = 5/12x - 5/39

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).