x^2-70x+1200=0

Solution for x^2-70x+1200=0 equation:

x^2-70x+1200=0

a = 1; b = -70; c = +1200;
Δ = b2-4ac
Δ = -702-4·1·1200
Δ = 100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{100}=10$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-70)-10}{2*1}=\frac{60}{2}
=30
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-70)+10}{2*1}=\frac{80}{2}
=40
$