4x*7x=12600

Solution for 4x*7x=12600 equation:

4x*7x=12600

We move all terms to the left:

4x*7x-(12600)=0

Wy multiply elements

28x^2-12600=0

a = 28; b = 0; c = -12600;
Δ = b2-4ac
Δ = 02-4·28·(-12600)
Δ = 1411200
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:

$\sqrt{\Delta}=\sqrt{1411200}=\sqrt{705600*2}=\sqrt{705600}*\sqrt{2}=840\sqrt{2}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-840\sqrt{2}}{2*28}=\frac{0-840\sqrt{2}}{56}
=-\frac{840\sqrt{2}}{56}
=-15\sqrt{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+840\sqrt{2}}{2*28}=\frac{0+840\sqrt{2}}{56}
=\frac{840\sqrt{2}}{56}
=15\sqrt{2}
$