(1+y)(2y-7)=0

Solution for (1+y)(2y-7)=0 equation:

(1+y)(2y-7)=0

We add all the numbers together, and all the variables

(y+1)(2y-7)=0

We multiply parentheses ..

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

We get rid of parentheses

2y^2-7y+2y-7=0

We add all the numbers together, and all the variables

2y^2-5y-7=0

a = 2; b = -5; c = -7;
Δ = b2-4ac
Δ = -52-4·2·(-7)
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-9}{2*2}=\frac{-4}{4}
=-1
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+9}{2*2}=\frac{14}{4}
=3+1/2
$