Solve the simultaneous equations: y = 2x + 1 and x + y = 7.
Answer and explanation
Correct answer: B. x = 2 and y = 5
- Step 1: Substitute y = 2x + 1 into the second equation: x + (2x + 1) = 7 => 3x + 1 = 7. Step 2. Solve for x: 3x = 6 => x = 2. Then find y: y = 2(2) + 1 = 5. Answer: x = 2 and y = 5. Why not the others: Checking x = 2, y = 5: 2 + 5 = 7 and 5 = 2(2) + 1. It satisfies both equations.
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