3x2+5x=7

Solution for 3x2+5x=7 equation:

3x^2+5x=7

We move all terms to the left:

3x^2+5x-(7)=0

a = 3; b = 5; c = -7;
Δ = b2-4ac
Δ = 52-4·3·(-7)
Δ = 109
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{-(5)-\sqrt{109}}{2*3}=\frac{-5-\sqrt{109}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+\sqrt{109}}{2*3}=\frac{-5+\sqrt{109}}{6}
$