all you have to do is multiply it to the two solutions
so say the factored quadratic is (x-4)(x+4), so the solutions are 4 and -4. just multiply the rad5 to those two answers.
Okay! well, if the exponents have the same base (ie 2^x-1=2^6-x) then you can set the exponents equal to each other. For your problems, you will have to manipulate the bases to get them to be the same... for example if you have 2^x-4=8, that also equals 2^x-4=2^3, so then x-4=3.