(70-7x)=(-2x)(-2x)

Solution for (70-7x)=(-2x)(-2x) equation:

(70-7x)=(-2x)(-2x)

We move all terms to the left:

(70-7x)-((-2x)(-2x))=0

We add all the numbers together, and all the variables

(-7x+70)-((-2x)(-2x))=0

We get rid of parentheses

-7x-((-2x)(-2x))+70=0

We multiply parentheses ..

-((+4x^2))-7x+70=0


We calculate terms in parentheses: -((+4x^2)), so:

(+4x^2)

We get rid of parentheses

4x^2

Back to the equation:

-(4x^2)


a = -4; b = -7; c = +70;
Δ = b2-4ac
Δ = -72-4·(-4)·70
Δ = 1169
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{-(-7)-\sqrt{1169}}{2*-4}=\frac{7-\sqrt{1169}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+\sqrt{1169}}{2*-4}=\frac{7+\sqrt{1169}}{-8}
$