(M-1)(-2)=-2(m-1)

Solution for (M-1)(-2)=-2(m-1) equation:

Simplifying
(M + -1)(-2) = -2(m + -1)

Reorder the terms:
(-1 + M)(-2) = -2(m + -1)

Reorder the terms for easier multiplication:
-2(-1 + M) = -2(m + -1)
(-1 * -2 + M * -2) = -2(m + -1)
(2 + -2M) = -2(m + -1)

Reorder the terms:
2 + -2M = -2(-1 + m)
2 + -2M = (-1 * -2 + m * -2)
2 + -2M = (2 + -2m)

Add '-2' to each side of the equation.
2 + -2 + -2M = 2 + -2 + -2m

Combine like terms: 2 + -2 = 0
0 + -2M = 2 + -2 + -2m
-2M = 2 + -2 + -2m

Combine like terms: 2 + -2 = 0
-2M = 0 + -2m
-2M = -2m

Solving
-2M = -2m

Solving for variable 'M'.

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

Divide each side by '-2'.
M = m

Simplifying
M = m