9x=(-27/7)

Solution for 9x=(-27/7) equation:

9x=(-27/7)

We move all terms to the left:

9x-((-27/7))=0

We multiply all the terms by the denominator


9x*7))-((-27=0

Wy multiply elements

63x^2-27=0

a = 63; b = 0; c = -27;
Δ = b2-4ac
Δ = 02-4·63·(-27)
Δ = 6804
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:

$\sqrt{\Delta}=\sqrt{6804}=\sqrt{324*21}=\sqrt{324}*\sqrt{21}=18\sqrt{21}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-18\sqrt{21}}{2*63}=\frac{0-18\sqrt{21}}{126}
=-\frac{18\sqrt{21}}{126}
=-\frac{\sqrt{21}}{7}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+18\sqrt{21}}{2*63}=\frac{0+18\sqrt{21}}{126}
=\frac{18\sqrt{21}}{126}
=\frac{\sqrt{21}}{7}
$