4x^2+3x=280

Solution for 4x^2+3x=280 equation:

4x^2+3x=280

We move all terms to the left:

4x^2+3x-(280)=0

a = 4; b = 3; c = -280;
Δ = b2-4ac
Δ = 32-4·4·(-280)
Δ = 4489
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4489}=67$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(3)-67}{2*4}=\frac{-70}{8}
=-8+3/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3)+67}{2*4}=\frac{64}{8}
=8
$