21/2x-3=2x-2

Solution for 21/2x-3=2x-2 equation:

21/2x-3=2x-2

We move all terms to the left:

21/2x-3-(2x-2)=0


Domain of the equation: 2x!=0

x!=0/2

x!=0

x∈R


We get rid of parentheses

21/2x-2x+2-3=0

We multiply all the terms by the denominator


-2x*2x+2*2x-3*2x+21=0

Wy multiply elements

-4x^2+4x-6x+21=0

We add all the numbers together, and all the variables

-4x^2-2x+21=0

a = -4; b = -2; c = +21;
Δ = b2-4ac
Δ = -22-4·(-4)·21
Δ = 340
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:

$\sqrt{\Delta}=\sqrt{340}=\sqrt{4*85}=\sqrt{4}*\sqrt{85}=2\sqrt{85}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-2)-2\sqrt{85}}{2*-4}=\frac{2-2\sqrt{85}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2)+2\sqrt{85}}{2*-4}=\frac{2+2\sqrt{85}}{-8}
$