3(x-9)(x+25)=0

Solution for 3(x-9)(x+25)=0 equation:

3(x-9)(x+25)=0

We multiply parentheses ..

3(+x^2+25x-9x-225)=0

We multiply parentheses

3x^2+75x-27x-675=0

We add all the numbers together, and all the variables

3x^2+48x-675=0

a = 3; b = 48; c = -675;
Δ = b2-4ac
Δ = 482-4·3·(-675)
Δ = 10404
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{10404}=102$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(48)-102}{2*3}=\frac{-150}{6}
=-25
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(48)+102}{2*3}=\frac{54}{6}
=9
$