3(5x2)=4(3x+9)

Solution for 3(5x2)=4(3x+9) equation:

3(5x^2)=4(3x+9)

We move all terms to the left:

3(5x^2)-(4(3x+9))=0


We calculate terms in parentheses: -(4(3x+9)), so:

4(3x+9)

We multiply parentheses

12x+36

Back to the equation:

-(12x+36)


We get rid of parentheses

35x^2-12x-36=0

a = 35; b = -12; c = -36;
Δ = b2-4ac
Δ = -122-4·35·(-36)
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-72}{2*35}=\frac{-60}{70}
=-6/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+72}{2*35}=\frac{84}{70}
=1+1/5
$