In order to solve for x, we need to clear the denominators :) To do that, we need to find a number that divides evenly by 3 and 4 (with no remainder). That is the Least Common Multiple: 12. A larger multiple that both 3 and 4 have in common like 24 or 60 would also work, but a smaller number is easier to work with, so we'll use 12. Start with the equation given in the problem:
Then we multiply by 12. Don't forget that we need to multiply both sides of the equation:
Then just distribute the 12 to each term inside the parentheses, and we get:
4x + 3x + 180 = 12x
Combine like terms, and we get:
7x + 180 = 12x
Subtract 7x from both sides to get the x terms all on one side:
180 = 5x
And divide both sides by 5 to get x on its own:
36 = x, and the answer is (C).
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