(y-9)(y-1)=0

Solution for (y-9)(y-1)=0 equation:

Simplifying
(y + -9)(y + -1) = 0

Reorder the terms:
(-9 + y)(y + -1) = 0

Reorder the terms:
(-9 + y)(-1 + y) = 0

Multiply (-9 + y) * (-1 + y)
(-9(-1 + y) + y(-1 + y)) = 0
((-1 * -9 + y * -9) + y(-1 + y)) = 0
((9 + -9y) + y(-1 + y)) = 0
(9 + -9y + (-1 * y + y * y)) = 0
(9 + -9y + (-1y + y2)) = 0

Combine like terms: -9y + -1y = -10y
(9 + -10y + y2) = 0

Solving
9 + -10y + y2 = 0

Solving for variable 'y'.

Factor a trinomial.
(1 + -1y)(9 + -1y) = 0

Subproblem 1
Set the factor '(1 + -1y)' equal to zero and attempt to solve:

Simplifying
1 + -1y = 0

Solving
1 + -1y = 0

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

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

Combine like terms: 1 + -1 = 0
0 + -1y = 0 + -1
-1y = 0 + -1

Combine like terms: 0 + -1 = -1
-1y = -1

Divide each side by '-1'.
y = 1

Simplifying
y = 1
Subproblem 2
Set the factor '(9 + -1y)' equal to zero and attempt to solve:

Simplifying
9 + -1y = 0

Solving
9 + -1y = 0

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

Add '-9' to each side of the equation.
9 + -9 + -1y = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -1y = 0 + -9
-1y = 0 + -9

Combine like terms: 0 + -9 = -9
-1y = -9

Divide each side by '-1'.
y = 9

Simplifying
y = 9
Solution
y = {1, 9}