x(5x+22)=15

Solution for x(5x+22)=15 equation:

x(5x+22)=15

We move all terms to the left:

x(5x+22)-(15)=0

We multiply parentheses

5x^2+22x-15=0

a = 5; b = 22; c = -15;
Δ = b2-4ac
Δ = 222-4·5·(-15)
Δ = 784
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{784}=28$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(22)-28}{2*5}=\frac{-50}{10}
=-5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(22)+28}{2*5}=\frac{6}{10}
=3/5
$