(4m+5)(m+1)=0

Solution for (4m+5)(m+1)=0 equation:

(4m+5)(m+1)=0

We multiply parentheses ..

(+4m^2+4m+5m+5)=0

We get rid of parentheses

4m^2+4m+5m+5=0

We add all the numbers together, and all the variables

4m^2+9m+5=0

a = 4; b = 9; c = +5;
Δ = b2-4ac
Δ = 92-4·4·5
Δ = 1
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1}=1$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(9)-1}{2*4}=\frac{-10}{8}
=-1+1/4
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+1}{2*4}=\frac{-8}{8}
=-1
$