(9m+1)(4m+5)=0

Solution for (9m+1)(4m+5)=0 equation:

(9m+1)(4m+5)=0

We multiply parentheses ..

(+36m^2+45m+4m+5)=0

We get rid of parentheses

36m^2+45m+4m+5=0

We add all the numbers together, and all the variables

36m^2+49m+5=0

a = 36; b = 49; c = +5;
Δ = b2-4ac
Δ = 492-4·36·5
Δ = 1681
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1681}=41$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(49)-41}{2*36}=\frac{-90}{72}
=-1+1/4
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(49)+41}{2*36}=\frac{-8}{72}
=-1/9
$