4/7x+15=3x

Solution for 4/7x+15=3x equation:

4/7x+15=3x

We move all terms to the left:

4/7x+15-(3x)=0


Domain of the equation: 7x!=0

x!=0/7

x!=0

x∈R


We add all the numbers together, and all the variables

-3x+4/7x+15=0

We multiply all the terms by the denominator


-3x*7x+15*7x+4=0

Wy multiply elements

-21x^2+105x+4=0

a = -21; b = 105; c = +4;
Δ = b2-4ac
Δ = 1052-4·(-21)·4
Δ = 11361
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{-(105)-\sqrt{11361}}{2*-21}=\frac{-105-\sqrt{11361}}{-42}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(105)+\sqrt{11361}}{2*-21}=\frac{-105+\sqrt{11361}}{-42}
$