(5+2x)(3+2x)=35

Solution for (5+2x)(3+2x)=35 equation:

(5+2x)(3+2x)=35

We move all terms to the left:

(5+2x)(3+2x)-(35)=0

We add all the numbers together, and all the variables

(2x+5)(2x+3)-35=0

We multiply parentheses ..

(+4x^2+6x+10x+15)-35=0

We get rid of parentheses

4x^2+6x+10x+15-35=0

We add all the numbers together, and all the variables

4x^2+16x-20=0

a = 4; b = 16; c = -20;
Δ = b2-4ac
Δ = 162-4·4·(-20)
Δ = 576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{576}=24$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-24}{2*4}=\frac{-40}{8}
=-5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+24}{2*4}=\frac{8}{8}
=1
$