I'm just guessing that your first equation might be
If it is, the answers are
So get your calculator working! Divide 8 by 15. Then find the square root. Then put a sign in front, because there will be two answers.
The second one, I think, might be:
If so, then you solve it like this:
How am I doing? Did I guess right?
. . . . .x^2 = 8/15
. . . . .(x)(3x) = -x^2 + 4
If so, then you can solve the first equation by taking the square root of each side of the equation, remembering the "plus-minus" on the right-hand side. You'll probably need to "rationalize the denominator" to get the answer in the "right" format.
For the second one, simplify the left-hand side to get 3x^2. Get the variable term together, and then divide 4x^2 = 4 on both sides by 4. Then you can solve by taking the square root of either side.