Solve.
-$\sqrt { x } + 1 = \sqrt { x + 7 }$
A) 9
B) 36
C) 3
D) $\varnothing$

Question

Quizplus · Accepted Answer

Squaring both sides of the equation gives $x + 2\sqrt { x } + 1 = x + 7$. Subtracting $x$ from both sides and then squaring both sides again gives $4x + 4\sqrt { x } = 36$. Dividing both sides by 4 gives $x + \sqrt { x } = 9$. Squaring both sides again gives $x^2 + 2x + 1 = 81$. Subtracting 81 from both sides gives $x^2 + 2x - 80 = 0$. Factoring gives $(x - 8)(x + 10) = 0$. Therefore, $x = 8$ or $x = -10$. Since $x$ must be nonnegative, the only solution is $x = 8$.

Solve - x+1=x+7\sqrt { x } + 1 = \sqrt { x + 7 }x​+1=x+7​

Solve
- $\sqrt { x } + 1 = \sqrt { x + 7 }$