3.5x+35=7.5x2

Solution for 3.5x+35=7.5x2 equation:

3.5x+35=7.5x^2

We move all terms to the left:

3.5x+35-(7.5x^2)=0

We get rid of parentheses

-7.5x^2+3.5x+35=0

a = -7.5; b = 3.5; c = +35;
Δ = b2-4ac
Δ = 3.52-4·(-7.5)·35
Δ = 1062.25
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{-(3.5)-\sqrt{1062.25}}{2*-7.5}=\frac{-3.5-\sqrt{1062.25}}{-15}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3.5)+\sqrt{1062.25}}{2*-7.5}=\frac{-3.5+\sqrt{1062.25}}{-15}
$