-1/4x-8=x+7

Solution for -1/4x-8=x+7 equation:

-1/4x-8=x+7

We move all terms to the left:

-1/4x-8-(x+7)=0


Domain of the equation: 4x!=0

x!=0/4

x!=0

x∈R


We get rid of parentheses

-1/4x-x-7-8=0

We multiply all the terms by the denominator


-x*4x-7*4x-8*4x-1=0

Wy multiply elements

-4x^2-28x-32x-1=0

We add all the numbers together, and all the variables

-4x^2-60x-1=0

a = -4; b = -60; c = -1;
Δ = b2-4ac
Δ = -602-4·(-4)·(-1)
Δ = 3584
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{3584}=\sqrt{256*14}=\sqrt{256}*\sqrt{14}=16\sqrt{14}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-60)-16\sqrt{14}}{2*-4}=\frac{60-16\sqrt{14}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-60)+16\sqrt{14}}{2*-4}=\frac{60+16\sqrt{14}}{-8}
$