0=x-4*7x^2

Solution for 0=x-4*7x^2 equation:

0=x-4*7x^2

We move all terms to the left:

0-(x-4*7x^2)=0

We add all the numbers together, and all the variables

-(x-4*7x^2)=0

We get rid of parentheses

-x+4*7x^2=0

We add all the numbers together, and all the variables

-1x+4*7x^2=0

Wy multiply elements

28x^2-1x=0

a = 28; b = -1; c = 0;
Δ = b2-4ac
Δ = -12-4·28·0
Δ = 1
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1}=1$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-1}{2*28}=\frac{0}{56}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+1}{2*28}=\frac{2}{56}
=1/28
$