What is the answer for 5/3010

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

I’m really confused and need to learn this

Write the factored form of this trinomial 9x^2+18x-7