(9/2)a+12=21

Solution for (9/2)a+12=21 equation:

(9/2)a+12=21

We move all terms to the left:

(9/2)a+12-(21)=0


Domain of the equation: 2)a!=0

a!=0/1

a!=0

a∈R


We add all the numbers together, and all the variables

(+9/2)a+12-21=0

We add all the numbers together, and all the variables

(+9/2)a-9=0

We multiply parentheses

9a^2-9=0

a = 9; b = 0; c = -9;
Δ = b2-4ac
Δ = 02-4·9·(-9)
Δ = 324
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{324}=18$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-18}{2*9}=\frac{-18}{18}
=-1
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+18}{2*9}=\frac{18}{18}
=1
$