-4x^2+10x+18=0

Solution for -4x^2+10x+18=0 equation:

-4x^2+10x+18=0

a = -4; b = 10; c = +18;
Δ = b2-4ac
Δ = 102-4·(-4)·18
Δ = 388
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{388}=\sqrt{4*97}=\sqrt{4}*\sqrt{97}=2\sqrt{97}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{97}}{2*-4}=\frac{-10-2\sqrt{97}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{97}}{2*-4}=\frac{-10+2\sqrt{97}}{-8}
$