(3m+7)(5m-9)=0

Solution for (3m+7)(5m-9)=0 equation:

(3m+7)(5m-9)=0

We multiply parentheses ..

(+15m^2-27m+35m-63)=0

We get rid of parentheses

15m^2-27m+35m-63=0

We add all the numbers together, and all the variables

15m^2+8m-63=0

a = 15; b = 8; c = -63;
Δ = b2-4ac
Δ = 82-4·15·(-63)
Δ = 3844
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3844}=62$
$m_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-62}{2*15}=\frac{-70}{30}
=-2+1/3
$
$m_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+62}{2*15}=\frac{54}{30}
=1+4/5
$