(X+5)(x+3)=92,5

Solution for (X+5)(x+3)=92,5 equation:

(X+5)(X+3)=92.5

We move all terms to the left:

(X+5)(X+3)-(92.5)=0

We add all the numbers together, and all the variables

(X+5)(X+3)-92.5=0

We multiply parentheses ..

(+X^2+3X+5X+15)-92.5=0

We get rid of parentheses

X^2+3X+5X+15-92.5=0

We add all the numbers together, and all the variables

X^2+8X-77.5=0

a = 1; b = 8; c = -77.5;
Δ = b2-4ac
Δ = 82-4·1·(-77.5)
Δ = 374
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-\sqrt{374}}{2*1}=\frac{-8-\sqrt{374}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+\sqrt{374}}{2*1}=\frac{-8+\sqrt{374}}{2}
$