(5y2-4)3=

Solution for (5y2-4)3= equation:

(5y^2-4)3=

We move all terms to the left:

(5y^2-4)3-()=0

We add all the numbers together, and all the variables

(5y^2-4)3=0

We multiply parentheses

15y^2-12=0

a = 15; b = 0; c = -12;
Δ = b2-4ac
Δ = 02-4·15·(-12)
Δ = 720
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{720}=\sqrt{144*5}=\sqrt{144}*\sqrt{5}=12\sqrt{5}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-12\sqrt{5}}{2*15}=\frac{0-12\sqrt{5}}{30}
=-\frac{12\sqrt{5}}{30}
=-\frac{2\sqrt{5}}{5}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+12\sqrt{5}}{2*15}=\frac{0+12\sqrt{5}}{30}
=\frac{12\sqrt{5}}{30}
=\frac{2\sqrt{5}}{5}
$