9x^2+10x-4=0

Solution for 9x^2+10x-4=0 equation:

9x^2+10x-4=0

a = 9; b = 10; c = -4;
Δ = b2-4ac
Δ = 102-4·9·(-4)
Δ = 244
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:

$\sqrt{\Delta}=\sqrt{244}=\sqrt{4*61}=\sqrt{4}*\sqrt{61}=2\sqrt{61}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{61}}{2*9}=\frac{-10-2\sqrt{61}}{18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{61}}{2*9}=\frac{-10+2\sqrt{61}}{18}
$