To solve an equation, use inverse operations.
Whatever operation is done to one side of the
equation must be done to the other side to make
an equivalent equation.
If a = b, then a + c = b + c.
If a = b, then a - c = b - c.
If a = b, then ac = bc.
If a = b, and c ≠ 0, then a / c = b / c.
n - 8 = 12 matches n =
â€œIf you add 8 to both sides, then n = 20.â€
2n + 3 = 15 matches n = 6.
â€œFirst subtract 3 from each side to get 2n = 12.
Then divide both sides by 2 to get n = 6.â€