(1.25+x)(0.75+x)/(2)=1.78*10^-5

Solution for (1.25+x)(0.75+x)/(2)=1.78*10^-5 equation:

(1.25+x)(0.75+x)/(2)=1.78*10^-5

We move all terms to the left:

(1.25+x)(0.75+x)/(2)-(1.78*10^-5)=0

We add all the numbers together, and all the variables

(x+1.25)(x+0.75)/2-(1.78*10^-5)=0

We add all the numbers together, and all the variables

(x+1.25)(x+0.75)/2-5-1.78E=0

We multiply parentheses ..

(+x^2+0.75x+1.25x+0.9375)/2-5-1.78E=0

We multiply all the terms by the denominator


(+x^2+0.75x+1.25x+0.9375)-5*2-(1.78E)*2=0

We add all the numbers together, and all the variables

(+x^2+0.75x+1.25x+0.9375)-5*2-(4.8385416546571)*2=0

We add all the numbers together, and all the variables

(+x^2+0.75x+1.25x+0.9375)-19.677083309314=0

We get rid of parentheses

x^2+0.75x+1.25x+0.9375-19.677083309314=0

We add all the numbers together, and all the variables

x^2+2x-18.739583309314=0

a = 1; b = 2; c = -18.739583309314;
Δ = b2-4ac
Δ = 22-4·1·(-18.739583309314)
Δ = 78.958333237256
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{-(2)-\sqrt{78.958333237256}}{2*1}=\frac{-2-\sqrt{78.958333237256}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+\sqrt{78.958333237256}}{2*1}=\frac{-2+\sqrt{78.958333237256}}{2}
$