x(3/4x)=1200

Solution for x(3/4x)=1200 equation:

x(3/4x)=1200

We move all terms to the left:

x(3/4x)-(1200)=0


Domain of the equation: 4x)!=0

x!=0/1

x!=0

x∈R


We add all the numbers together, and all the variables

x(+3/4x)-1200=0

We multiply parentheses

3x^2-1200=0

a = 3; b = 0; c = -1200;
Δ = b2-4ac
Δ = 02-4·3·(-1200)
Δ = 14400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{14400}=120$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-120}{2*3}=\frac{-120}{6}
=-20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+120}{2*3}=\frac{120}{6}
=20
$