7x*3x=525

Solution for 7x*3x=525 equation:

7x*3x=525

We move all terms to the left:

7x*3x-(525)=0

Wy multiply elements

21x^2-525=0

a = 21; b = 0; c = -525;
Δ = b2-4ac
Δ = 02-4·21·(-525)
Δ = 44100
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{44100}=210$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-210}{2*21}=\frac{-210}{42}
=-5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+210}{2*21}=\frac{210}{42}
=5
$