Question

Which quantity makes the equation true?
x + 3x + _______ = 7x

Answer 1

Answer: C. 3x

Explanation:

Since x and 3x both have x, you can add them together to get 4x (if there is x by itself, it really means that there is one of it, so it would be 1x.)

Then, you subtract 7x by 4x, which gives you the answer, 3x. You could also solving it by asking yourself: What number plus 4x equals 7x, which would give you 3x.

Answer 2

Explanation:

C) 3X