5(x^2+2x)=73

Solution for 5(x^2+2x)=73 equation:

5(x^2+2x)=73

We move all terms to the left:

5(x^2+2x)-(73)=0

We multiply parentheses

5x^2+10x-73=0

a = 5; b = 10; c = -73;
Δ = b2-4ac
Δ = 102-4·5·(-73)
Δ = 1560
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:

$\sqrt{\Delta}=\sqrt{1560}=\sqrt{4*390}=\sqrt{4}*\sqrt{390}=2\sqrt{390}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{390}}{2*5}=\frac{-10-2\sqrt{390}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{390}}{2*5}=\frac{-10+2\sqrt{390}}{10}
$