x= radical x+13+7 is what approx. the solution to th nearest hundredth.
X = sqrt(x+13+7).
Square both sides:
x^2 = x+13+7
x^2 - x - 20 = 0
C = -20 = -5*4.
(x-5)(x+4) = 0.
x-5 = 0
x = 5.
x+4 = 0
x = -4.
Solution set: X = 5, and X = -4.