X=-16x^2+85x

Solution for X=-16x^2+85x equation:

X=-16X^2+85X

We move all terms to the left:

X-(-16X^2+85X)=0

We get rid of parentheses

16X^2-85X+X=0

We add all the numbers together, and all the variables

16X^2-84X=0

a = 16; b = -84; c = 0;
Δ = b2-4ac
Δ = -842-4·16·0
Δ = 7056
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{7056}=84$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-84)-84}{2*16}=\frac{0}{32}
=0
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-84)+84}{2*16}=\frac{168}{32}
=5+1/4
$