(13y+4)(11y+7)=0

Solution for (13y+4)(11y+7)=0 equation:

(13y+4)(11y+7)=0

We multiply parentheses ..

(+143y^2+91y+44y+28)=0

We get rid of parentheses

143y^2+91y+44y+28=0

We add all the numbers together, and all the variables

143y^2+135y+28=0

a = 143; b = 135; c = +28;
Δ = b2-4ac
Δ = 1352-4·143·28
Δ = 2209
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2209}=47$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(135)-47}{2*143}=\frac{-182}{286}
=-7/11
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(135)+47}{2*143}=\frac{-88}{286}
=-4/13
$