15-3x=5x2

Solution for 15-3x=5x2 equation:

15-3x=5x^2

We move all terms to the left:

15-3x-(5x^2)=0

determiningTheFunctionDomain
-5x^2-3x+15=0

a = -5; b = -3; c = +15;
Δ = b2-4ac
Δ = -32-4·(-5)·15
Δ = 309
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{309}}{2*-5}=\frac{3-\sqrt{309}}{-10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{309}}{2*-5}=\frac{3+\sqrt{309}}{-10}
$