An=a^1+(n-1)d

Solution for An=a^1+(n-1)d equation:

Simplifying
An = a + (n + -1) * d

Reorder the terms:
nA = a + (-1 + n) * d

Reorder the terms for easier multiplication:
nA = a + d(-1 + n)
nA = a + (-1 * d + n * d)
nA = a + (-1d + dn)

Solving
nA = a + -1d + dn

Solving for variable 'n'.

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

Add '-1dn' to each side of the equation.
-1dn + nA = a + -1d + dn + -1dn

Combine like terms: dn + -1dn = 0
-1dn + nA = a + -1d + 0
-1dn + nA = a + -1d

Reorder the terms:
-1a + d + -1dn + nA = a + -1d + -1a + d

Reorder the terms:
-1a + d + -1dn + nA = a + -1a + -1d + d

Combine like terms: a + -1a = 0
-1a + d + -1dn + nA = 0 + -1d + d
-1a + d + -1dn + nA = -1d + d

Combine like terms: -1d + d = 0
-1a + d + -1dn + nA = 0

The solution to this equation could not be determined.