-3x2+15x=7

Solution for -3x2+15x=7 equation:

-3x^2+15x=7

We move all terms to the left:

-3x^2+15x-(7)=0

a = -3; b = 15; c = -7;
Δ = b2-4ac
Δ = 152-4·(-3)·(-7)
Δ = 141
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-\sqrt{141}}{2*-3}=\frac{-15-\sqrt{141}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+\sqrt{141}}{2*-3}=\frac{-15+\sqrt{141}}{-6}
$