0.9(x+1.4)1.8x=0.6(x-0.7)+4.2

Solution for 0.9(x+1.4)1.8x=0.6(x-0.7)+4.2 equation:

0.9(x+1.4)1.8x=0.6(x-0.7)+4.2

We move all terms to the left:

0.9(x+1.4)1.8x-(0.6(x-0.7)+4.2)=0

We multiply parentheses

0x^2+0x-(0.6(x-0.7)+4.2)=0


We calculate terms in parentheses: -(0.6(x-0.7)+4.2), so:

0.6(x-0.7)+4.2

We multiply parentheses

0.6x-0.42+4.2

We add all the numbers together, and all the variables

0.6x+3.78

Back to the equation:

-(0.6x+3.78)


We add all the numbers together, and all the variables

x^2+x-(0.6x+3.78)=0

We get rid of parentheses

x^2+x-0.6x-3.78=0

We add all the numbers together, and all the variables

x^2+0.4x-3.78=0

a = 1; b = 0.4; c = -3.78;
Δ = b2-4ac
Δ = 0.42-4·1·(-3.78)
Δ = 15.28
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{-(0.4)-\sqrt{15.28}}{2*1}=\frac{-0.4-\sqrt{15.28}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.4)+\sqrt{15.28}}{2*1}=\frac{-0.4+\sqrt{15.28}}{2}
$