-2x^2=-34x+140

Solution for -2x^2=-34x+140 equation:

-2x^2=-34x+140

We move all terms to the left:

-2x^2-(-34x+140)=0

We get rid of parentheses

-2x^2+34x-140=0

a = -2; b = 34; c = -140;
Δ = b2-4ac
Δ = 342-4·(-2)·(-140)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(34)-6}{2*-2}=\frac{-40}{-4}
=+10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(34)+6}{2*-2}=\frac{-28}{-4}
=+7
$