2x^2/5+4x+10=90

Solution for 2x^2/5+4x+10=90 equation:

2x^2/5+4x+10=90

We move all terms to the left:

2x^2/5+4x+10-(90)=0

We add all the numbers together, and all the variables

2x^2/5+4x-80=0

We multiply all the terms by the denominator


2x^2+4x*5-80*5=0

We add all the numbers together, and all the variables

2x^2+4x*5-400=0

Wy multiply elements

2x^2+20x-400=0

a = 2; b = 20; c = -400;
Δ = b2-4ac
Δ = 202-4·2·(-400)
Δ = 3600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3600}=60$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-60}{2*2}=\frac{-80}{4}
=-20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+60}{2*2}=\frac{40}{4}
=10
$