-16x^2+128x=87

Solution for -16x^2+128x=87 equation:

-16x^2+128x=87

We move all terms to the left:

-16x^2+128x-(87)=0

a = -16; b = 128; c = -87;
Δ = b2-4ac
Δ = 1282-4·(-16)·(-87)
Δ = 10816
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{10816}=104$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(128)-104}{2*-16}=\frac{-232}{-32}
=7+1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(128)+104}{2*-16}=\frac{-24}{-32}
=3/4
$