(8y^2-5y+4)-(4y^2-5y+8)=

Solution for (8y^2-5y+4)-(4y^2-5y+8)= equation:

Simplifying
(8y2 + -5y + 4) + -1(4y2 + -5y + 8) = 0

Reorder the terms:
(4 + -5y + 8y2) + -1(4y2 + -5y + 8) = 0

Remove parenthesis around (4 + -5y + 8y2)
4 + -5y + 8y2 + -1(4y2 + -5y + 8) = 0

Reorder the terms:
4 + -5y + 8y2 + -1(8 + -5y + 4y2) = 0
4 + -5y + 8y2 + (8 * -1 + -5y * -1 + 4y2 * -1) = 0
4 + -5y + 8y2 + (-8 + 5y + -4y2) = 0

Reorder the terms:
4 + -8 + -5y + 5y + 8y2 + -4y2 = 0

Combine like terms: 4 + -8 = -4
-4 + -5y + 5y + 8y2 + -4y2 = 0

Combine like terms: -5y + 5y = 0
-4 + 0 + 8y2 + -4y2 = 0
-4 + 8y2 + -4y2 = 0

Combine like terms: 8y2 + -4y2 = 4y2
-4 + 4y2 = 0

Solving
-4 + 4y2 = 0

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Add '4' to each side of the equation.
-4 + 4 + 4y2 = 0 + 4

Combine like terms: -4 + 4 = 0
0 + 4y2 = 0 + 4
4y2 = 0 + 4

Combine like terms: 0 + 4 = 4
4y2 = 4

Divide each side by '4'.
y2 = 1

Simplifying
y2 = 1

Take the square root of each side:
y = {-1, 1}