y^2+7y=144

Solution for y^2+7y=144 equation:

y^2+7y=144

We move all terms to the left:

y^2+7y-(144)=0

a = 1; b = 7; c = -144;
Δ = b2-4ac
Δ = 72-4·1·(-144)
Δ = 625
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{625}=25$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-25}{2*1}=\frac{-32}{2}
=-16
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+25}{2*1}=\frac{18}{2}
=9
$