Answer:
x = 9
Explanation:
Solving radical equations:
√x + 7 - 1 = x
√x + 6 = x
Isolate √x,
√x = x - 6
Square both sides,
(√x)² = (x - 6)²
Use identity (a -b)² = a² - 2ab + b²
x = x² - 2*x*6 + 6²
x = x² - 12x + 36
x² - 12x + 36 - x = 0
x² - 13x + 36 = 0
We look for two integers which when added give (-13) and when multiplied gives 36.
So, the factors are (-9) and (-4).
-9 + (-4) = -13 & (-9)*(-4) = 36.
Rewrite the middle term using the factors.
x² - 13x + 36 = x² - 9x - 4x + 36
Take out the common factor 'x' from first and second term & take out the common factor (-4) from third and fourth term.
=x(x -9) -4(x - 9)
= (x -9)(x- 4)
x - 9 = 0 ; x - 4 = 0
x = 9 ; x = 4
But 4 doest not satisfy the equation. So, only 9 is the solution.