How do you solve sqrt( x + 1) =x - 5√x+1=x−5?
1 Answer
Apr 22, 2016
Square both sides, solve the resulting quadratic, then check the solutions to find valid solution:
x = 8x=8
Explanation:
First square both sides, noting that this may introduce spurious solutions, to get:
x+1 = x^2-10x+25x+1=x2−10x+25
Subtract
0 = x^2-11x+24 = (x-3)(x-8)0=x2−11x+24=(x−3)(x−8)
So
The solution
The solution
sqrt(8+1) = sqrt(9) = 3 = 8 - 5√8+1=√9=3=8−5