7x^2=28-3x

Solution for 7x^2=28-3x equation:

7x^2=28-3x

We move all terms to the left:

7x^2-(28-3x)=0

We add all the numbers together, and all the variables

7x^2-(-3x+28)=0

We get rid of parentheses

7x^2+3x-28=0

a = 7; b = 3; c = -28;
Δ = b2-4ac
Δ = 32-4·7·(-28)
Δ = 793
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-\sqrt{793}}{2*7}=\frac{-3-\sqrt{793}}{14}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+\sqrt{793}}{2*7}=\frac{-3+\sqrt{793}}{14}
$