7x*13x=30

Solution for 7x*13x=30 equation:

7x*13x=30

We move all terms to the left:

7x*13x-(30)=0

Wy multiply elements

91x^2-30=0

a = 91; b = 0; c = -30;
Δ = b2-4ac
Δ = 02-4·91·(-30)
Δ = 10920
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:

$\sqrt{\Delta}=\sqrt{10920}=\sqrt{4*2730}=\sqrt{4}*\sqrt{2730}=2\sqrt{2730}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-2\sqrt{2730}}{2*91}=\frac{0-2\sqrt{2730}}{182}
=-\frac{2\sqrt{2730}}{182}
=-\frac{\sqrt{2730}}{91}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+2\sqrt{2730}}{2*91}=\frac{0+2\sqrt{2730}}{182}
=\frac{2\sqrt{2730}}{182}
=\frac{\sqrt{2730}}{91}
$