(3b+5)(3b-5)=24

Solution for (3b+5)(3b-5)=24 equation:

(3b+5)(3b-5)=24

We move all terms to the left:

(3b+5)(3b-5)-(24)=0

We use the square of the difference formula

9b^2-25-24=0

We add all the numbers together, and all the variables

9b^2-49=0

a = 9; b = 0; c = -49;
Δ = b2-4ac
Δ = 02-4·9·(-49)
Δ = 1764
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1764}=42$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-42}{2*9}=\frac{-42}{18}
=-2+1/3
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+42}{2*9}=\frac{42}{18}
=2+1/3
$