Y=-7x(-5x+11)+15

Solution for Y=-7x(-5x+11)+15 equation:

=-7Y(-5Y+11)+15

We move all terms to the left:

-(-7Y(-5Y+11)+15)=0


We calculate terms in parentheses: -(-7Y(-5Y+11)+15), so:

-7Y(-5Y+11)+15

We multiply parentheses

35Y^2-77Y+15

Back to the equation:

-(35Y^2-77Y+15)


We get rid of parentheses

-35Y^2+77Y-15=0

a = -35; b = 77; c = -15;
Δ = b2-4ac
Δ = 772-4·(-35)·(-15)
Δ = 3829
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(77)-\sqrt{3829}}{2*-35}=\frac{-77-\sqrt{3829}}{-70}
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(77)+\sqrt{3829}}{2*-35}=\frac{-77+\sqrt{3829}}{-70}
$