(3x+)(4x-10)=0

Solution for (3x+)(4x-10)=0 equation:

(3x+)(4x-10)=0

We add all the numbers together, and all the variables

(+3x)(4x-10)=0

We multiply parentheses ..

(+12x^2-30x)=0

We get rid of parentheses

12x^2-30x=0

a = 12; b = -30; c = 0;
Δ = b2-4ac
Δ = -302-4·12·0
Δ = 900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{900}=30$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-30)-30}{2*12}=\frac{0}{24}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-30)+30}{2*12}=\frac{60}{24}
=2+1/2
$