(X+0.25)(3x+0.9)=0

Solution for (X+0.25)(3x+0.9)=0 equation:

(X+0.25)(3X+0.9)=0

We multiply parentheses ..

(+3X^2+0.9X+0.75X+0.225)=0

We get rid of parentheses

3X^2+0.9X+0.75X+0.225=0

We add all the numbers together, and all the variables

3X^2+1.65X+0.225=0

a = 3; b = 1.65; c = +0.225;
Δ = b2-4ac
Δ = 1.652-4·3·0.225
Δ = 0.0225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1.65)-\sqrt{0.0225}}{2*3}=\frac{-1.65-\sqrt{0.0225}}{6}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1.65)+\sqrt{0.0225}}{2*3}=\frac{-1.65+\sqrt{0.0225}}{6}
$