Question

$x^{2}$-8x+7=0

Answer 1

-8x+7=0

Δ= 36

x1 = 7  ; x2 = 1

Answer 2

                                       $x^2 - 8x +7 =0$

Δ = $b^2 - 4 a . c$

Δ = $( - 8 )^2 - 4. 1 . 7 = 64 - 28 = 36$


$x = 8 +- \frac{6}{2} \\\\ x_1 = 8 - \frac{6}{2} = 1 \\\\ x_2 = 8 + \frac{6}{2} = 7$