-9x+7=25+2(5-x)X+-4

Solution for -9x+7=25+2(5-x)X+-4 equation:

-9x+7=25+2(5-x)x+-4

We move all terms to the left:

-9x+7-(25+2(5-x)x+-4)=0

We add all the numbers together, and all the variables

-9x-(25+2(-1x+5)x+-4)+7=0

We use the square of the difference formula

-9x-(25+2(-1x+5)x-4)+7=0


We calculate terms in parentheses: -(25+2(-1x+5)x-4), so:

25+2(-1x+5)x-4

determiningTheFunctionDomain
2(-1x+5)x+25-4

We add all the numbers together, and all the variables

2(-1x+5)x+21

We multiply parentheses

-2x^2+10x+21

Back to the equation:

-(-2x^2+10x+21)


We get rid of parentheses

2x^2-10x-9x-21+7=0

We add all the numbers together, and all the variables

2x^2-19x-14=0

a = 2; b = -19; c = -14;
Δ = b2-4ac
Δ = -192-4·2·(-14)
Δ = 473
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{-(-19)-\sqrt{473}}{2*2}=\frac{19-\sqrt{473}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-19)+\sqrt{473}}{2*2}=\frac{19+\sqrt{473}}{4}
$