Answer:
Step-by-step explanation: We can begin by rewriting the equation. That would look like so:
3/9 = x/12
We need to solve for x. Our first step is to identify a common denominator. Let's list the multiples of each denominator.
9: 9, 18, 27, 36
12: 12, 24, 36
Our common denominator is 36.
Now, let's cross multiply:
3 x 12 = 36
9 x ? = 36
36 ÷ 9 = 4
x = 4
Final answer: 3/9 = 4/12, where x = 4.