Y-1=m(x-a)

Solution for Y-1=m(x-a) equation:

Simplifying
Y + -1 = m(x + -1a)

Reorder the terms:
-1 + Y = m(x + -1a)

Reorder the terms:
-1 + Y = m(-1a + x)
-1 + Y = (-1a * m + x * m)
-1 + Y = (-1am + mx)

Solving
-1 + Y = -1am + mx

Solving for variable 'Y'.

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

Add '1' to each side of the equation.
-1 + 1 + Y = -1am + 1 + mx

Combine like terms: -1 + 1 = 0
0 + Y = -1am + 1 + mx
Y = -1am + 1 + mx

Reorder the terms:
Y = 1 + -1am + mx

Simplifying
Y = 1 + -1am + mx