Answer:
x = 12
Explanation:
There are several steps involved to solve this. I'll put each step separate so you can easily understand.
Step 1: Set up a proportion

Step 2: Cross multiply
7x = 7 x 12
7x = 84
x = 12
Step 3: Check
7 x 12 = 7 x 12
84 = 84 ✔
Step 4: Answer
x = 12
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