A=15x^2-22x+8

Solution for A=15x^2-22x+8 equation:

=15A^2-22A+8

We move all terms to the left:

-(15A^2-22A+8)=0

We get rid of parentheses

-15A^2+22A-8=0

a = -15; b = 22; c = -8;
Δ = b2-4ac
Δ = 222-4·(-15)·(-8)
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$A_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$A_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$A_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(22)-2}{2*-15}=\frac{-24}{-30}
=4/5
$
$A_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(22)+2}{2*-15}=\frac{-20}{-30}
=2/3
$