The numbers that I'm putting in the quadratic formula are too big and come out in decimals! Help!

(5x-2)^2 = 3
3

I'm assuming your starting equation is

\frac{(5x - 2)^2}{3} = 3

This implies

(5x - 2)^2 = 9

which in turn leads to two equations...

(5x - 2) = 3 and (5x - 2) = -3

Each of those will have its own unique solution for x. Be sure to wrap up by verifying that both of the solutions do indeed satisfy your original equation.

Where does the -3 come from, I understand (5x-2)=3 but were does (5x-2)=-3 come from seeing that the 9 is a positive?

No, 5x-2 = sqrt(9)
sqrt(9) has 2roots
3 and -3

3*3 = 9 and -3 * -3 = 9