Question

If $x>0$, and $x^2-6x-7=0$, what is the value of $x$?

• A. 5
• B. 6
• C. 7
• D. 4

Answer 1

The correct option is C 7

Given, $x^2-6x-7=0$

$\Rightarrow x^2-7x+x-7=0$

$\Rightarrow x(x-7)+1(x-7)=0$

$\Rightarrow (x-7)(x+1)=0$

$\Rightarrow x=7,-1$

As $x>0$ then $x=7$