1/8x+x=-9

Solution for 1/8x+x=-9 equation:

1/8x+x=-9

We move all terms to the left:

1/8x+x-(-9)=0


Domain of the equation: 8x!=0

x!=0/8

x!=0

x∈R


We add all the numbers together, and all the variables

x+1/8x+9=0

We multiply all the terms by the denominator


x*8x+9*8x+1=0

Wy multiply elements

8x^2+72x+1=0

a = 8; b = 72; c = +1;
Δ = b2-4ac
Δ = 722-4·8·1
Δ = 5152
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:

$\sqrt{\Delta}=\sqrt{5152}=\sqrt{16*322}=\sqrt{16}*\sqrt{322}=4\sqrt{322}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(72)-4\sqrt{322}}{2*8}=\frac{-72-4\sqrt{322}}{16}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(72)+4\sqrt{322}}{2*8}=\frac{-72+4\sqrt{322}}{16}
$