Question

Using the quadratic formula to solve 7x^2-x=7, what are the values of x?

Answer 1

Quadratic equation is $x= \frac{-b {\pm} \sqrt{ b^{2}-4ac}}{2a}$ WHEN 
$a x^{2} +bx+c=0$

So, to make this true subtract 7 from each side. 

The equation is now 7$x^{2}$ - x - 7 = 0 

Values for a, b, and c: a = 7, b = -1, c = -7 

Plug these variables into the quadratic equation. 

$x= \frac{1 {\pm} \sqrt{ -1^{2}-4*7*-7}}{2*-7}$ 

Square -1 to get 1 and multiply -4 x 7 x -7 to get 196. 

$x= \frac{1 {\pm} \sqrt{1+196}}{2*-7}$

Multiply 2 x -7 to get -14, the denominator, and add 1 to 196. 

$x= \frac{1 {\pm} \sqrt{197}}{-14}$ 

Since 197 is not a square number, and I don't know if you want to leave it in radical form or not, I will just because it's easier to understand. 

Hope this helps!