-25+2X^2+x+5^2+20+5^2=100

Solution for -25+2X^2+x+5^2+20+5^2=100 equation:

-25+2X^2+X+5^2+20+5^2=100

We move all terms to the left:

-25+2X^2+X+5^2+20+5^2-(100)=0

determiningTheFunctionDomain
2X^2+X-25+20-100+5^2+5^2=0

We add all the numbers together, and all the variables

2X^2+X-55=0

a = 2; b = 1; c = -55;
Δ = b2-4ac
Δ = 12-4·2·(-55)
Δ = 441
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{441}=21$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1)-21}{2*2}=\frac{-22}{4}
=-5+1/2
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1)+21}{2*2}=\frac{20}{4}
=5
$