(7y^2-4y+8)-(8y^2-4y+2)=

Solution for (7y^2-4y+8)-(8y^2-4y+2)= equation:

Simplifying
(7y2 + -4y + 8) + -1(8y2 + -4y + 2) = 0

Reorder the terms:
(8 + -4y + 7y2) + -1(8y2 + -4y + 2) = 0

Remove parenthesis around (8 + -4y + 7y2)
8 + -4y + 7y2 + -1(8y2 + -4y + 2) = 0

Reorder the terms:
8 + -4y + 7y2 + -1(2 + -4y + 8y2) = 0
8 + -4y + 7y2 + (2 * -1 + -4y * -1 + 8y2 * -1) = 0
8 + -4y + 7y2 + (-2 + 4y + -8y2) = 0

Reorder the terms:
8 + -2 + -4y + 4y + 7y2 + -8y2 = 0

Combine like terms: 8 + -2 = 6
6 + -4y + 4y + 7y2 + -8y2 = 0

Combine like terms: -4y + 4y = 0
6 + 0 + 7y2 + -8y2 = 0
6 + 7y2 + -8y2 = 0

Combine like terms: 7y2 + -8y2 = -1y2
6 + -1y2 = 0

Solving
6 + -1y2 = 0

Solving for variable 'y'.

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

Add '-6' to each side of the equation.
6 + -6 + -1y2 = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -1y2 = 0 + -6
-1y2 = 0 + -6

Combine like terms: 0 + -6 = -6
-1y2 = -6

Divide each side by '-1'.
y2 = 6

Simplifying
y2 = 6

Take the square root of each side:
y = {-2.449489743, 2.449489743}