42x^2=378

Solution for 42x^2=378 equation:

42x^2=378

We move all terms to the left:

42x^2-(378)=0

a = 42; b = 0; c = -378;
Δ = b2-4ac
Δ = 02-4·42·(-378)
Δ = 63504
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{63504}=252$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-252}{2*42}=\frac{-252}{84}
=-3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+252}{2*42}=\frac{252}{84}
=3
$