X=1/10x+9

Solution for X=1/10x+9 equation:

X=1/10X+9

We move all terms to the left:

X-(1/10X+9)=0


Domain of the equation: 10X+9)!=0

X∈R


We get rid of parentheses

X-1/10X-9=0

We multiply all the terms by the denominator


X*10X-9*10X-1=0

Wy multiply elements

10X^2-90X-1=0

a = 10; b = -90; c = -1;
Δ = b2-4ac
Δ = -902-4·10·(-1)
Δ = 8140
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:

$\sqrt{\Delta}=\sqrt{8140}=\sqrt{4*2035}=\sqrt{4}*\sqrt{2035}=2\sqrt{2035}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-90)-2\sqrt{2035}}{2*10}=\frac{90-2\sqrt{2035}}{20}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-90)+2\sqrt{2035}}{2*10}=\frac{90+2\sqrt{2035}}{20}
$