(5y+8)-(-4y^2-9y+8)=

Solution for (5y+8)-(-4y^2-9y+8)= equation:

(5y+8)-(-4y^2-9y+8)=

We move all terms to the left:

(5y+8)-(-4y^2-9y+8)-()=0

We add all the numbers together, and all the variables

-(-4y^2-9y+8)+(5y+8)=0

We get rid of parentheses

4y^2+9y+5y-8+8=0

We add all the numbers together, and all the variables

4y^2+14y=0

a = 4; b = 14; c = 0;
Δ = b2-4ac
Δ = 142-4·4·0
Δ = 196
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{196}=14$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-14}{2*4}=\frac{-28}{8}
=-3+1/2
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+14}{2*4}=\frac{0}{8}
=0
$