28x^2=7*16

Solution for 28x^2=7*16 equation:

28x^2=7*16

We move all terms to the left:

28x^2-(7*16)=0

We add all the numbers together, and all the variables

28x^2-112=0

a = 28; b = 0; c = -112;
Δ = b2-4ac
Δ = 02-4·28·(-112)
Δ = 12544
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{12544}=112$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-112}{2*28}=\frac{-112}{56}
=-2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+112}{2*28}=\frac{112}{56}
=2
$