70=(1/2)x(x-4)

Solution for 70=(1/2)x(x-4) equation:

70=(1/2)x(x-4)

We move all terms to the left:

70-((1/2)x(x-4))=0


Domain of the equation: 2)x(x-4))!=0

x∈R


We add all the numbers together, and all the variables

-((+1/2)x(x-4))+70=0

We multiply all the terms by the denominator


-((+1+70*2)x(x-4))=0


We calculate terms in parentheses: -((+1+70*2)x(x-4)), so:

(+1+70*2)x(x-4)

We add all the numbers together, and all the variables

141x(x-4)

We multiply parentheses

141x^2-564x

Back to the equation:

-(141x^2-564x)


We get rid of parentheses

-141x^2+564x=0

a = -141; b = 564; c = 0;
Δ = b2-4ac
Δ = 5642-4·(-141)·0
Δ = 318096
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{318096}=564$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(564)-564}{2*-141}=\frac{-1128}{-282}
=+4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(564)+564}{2*-141}=\frac{0}{-282}
=0
$