(X-3)(x+4)=(2x+4)-1

Solution for (X-3)(x+4)=(2x+4)-1 equation:

(X-3)(X+4)=(2X+4)-1

We move all terms to the left:

(X-3)(X+4)-((2X+4)-1)=0

We multiply parentheses ..

(+X^2+4X-3X-12)-((2X+4)-1)=0


We calculate terms in parentheses: -((2X+4)-1), so:

(2X+4)-1

We get rid of parentheses

2X+4-1

We add all the numbers together, and all the variables

2X+3

Back to the equation:

-(2X+3)


We get rid of parentheses

X^2+4X-3X-2X-12-3=0

We add all the numbers together, and all the variables

X^2-1X-15=0

a = 1; b = -1; c = -15;
Δ = b2-4ac
Δ = -12-4·1·(-15)
Δ = 61
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{-(-1)-\sqrt{61}}{2*1}=\frac{1-\sqrt{61}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+\sqrt{61}}{2*1}=\frac{1+\sqrt{61}}{2}
$