X - 12 = 30
To solve for x in this equation, we want to get x by itself on the left side of the equation. Since 12 is being subtracted from x, to get x by itself, we need to add 12 to the left side of the equation. If we add 12 to the left side, we must also add 12 to the right side.
On the left side, -12 and +12 cancel each other out so we are simply left with x. On the right side, 30 + 12 is 42 so we have x = 42.
It's important to understand that we can check our answer by substituting 42 back into the original equation.
So we have (42) - 12 = 30.
42 - 12 is 30 so we have 30 = 30 which is a true statement so our answer, x = 42, is correct.
