3a2-11=21+a2

Solution for 3a2-11=21+a2 equation:

3a^2-11=21+a2

We move all terms to the left:

3a^2-11-(21+a2)=0

We add all the numbers together, and all the variables

3a^2-(+a^2+21)-11=0

We get rid of parentheses

3a^2-a^2-21-11=0

We add all the numbers together, and all the variables

2a^2-32=0

a = 2; b = 0; c = -32;
Δ = b2-4ac
Δ = 02-4·2·(-32)
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-16}{2*2}=\frac{-16}{4}
=-4
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+16}{2*2}=\frac{16}{4}
=4
$