Solve . What is the value of ?

Answer and explanation

Correct answer: C. 12

  1. Step 1: Eliminate one unknown by combining the two equations; this gives and .
  2. Step 2: Check in the first equation: .
  3. Step 3: Hence .
Answer
12.
Why not the others: 5: that is only the value of . 7: that is only the value of . 47: wrong combination of the solutions.

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