Question

Solve the equation by completing the square. 2x-18x+58=0

Answer 1

$x^{2} -18x+58=0$

We have got quadratic equation. We calculate it by using Δ.

$\Delta=(-18)^{2} -4*1*58=324-232=92>0$
$\sqrt{\Delta} = \sqrt{92} =2 \sqrt{23}$

$x_1= \frac{-b- \sqrt{\Delta} }{2a} = \frac{18-2 \sqrt{23} }{2} =9- \sqrt{23}$
∨
$x_2= \frac{-b+ \sqrt{\Delta} }{2a} = \frac{18+2 \sqrt{23} }{2} =9+ \sqrt{23}$

Hope it helps :)