Answer: "7 is a solution to the original equation. The value –1 is an extraneous solution."
Explanation:
The equation
can be solved by squaring both sides:
![x^2 = 6x + 7\\\\x^2 - 6x - 7 = 0\\\\(x-7)(x+1) = 0](https://img.qammunity.org/2021/formulas/mathematics/high-school/67epxvyfer6qgemujnze9c07blnoyjyfy2.png)
We can see that -1 and 7 are solutions, but make sure they are not extraneous by substituting them in the original equation:
![1 = √(-1)\\ 7 = √(49)](https://img.qammunity.org/2021/formulas/mathematics/high-school/9sl0mv0i23f7whnntc554hg9vguo5fuyk7.png)
The square root of 49 equals 7, but the square root of -1 is an imaginary number.
The correct choice is "7 is a solution to the original equation. The value –1 is an extraneous solution."