Y=20x^2+140x+240

Solution for Y=20x^2+140x+240 equation:

=20Y^2+140Y+240

We move all terms to the left:

-(20Y^2+140Y+240)=0

We get rid of parentheses

-20Y^2-140Y-240=0

a = -20; b = -140; c = -240;
Δ = b2-4ac
Δ = -1402-4·(-20)·(-240)
Δ = 400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{400}=20$
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-140)-20}{2*-20}=\frac{120}{-40}
=-3
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-140)+20}{2*-20}=\frac{160}{-40}
=-4
$