The curve y = x^2 - 6x + 5 has a turning point. What are its coordinates?
Answer and explanation
Correct answer: A. (3, -4)
- Step 1: dy/dx = 2x - 6 = 0 gives x = 3. Step 2. y = 9 - 18 + 5 = -4, so the turning point is (3, -4). Answer: (3, -4). Why not the others: (3, 4): The y-value is negative: 9 - 18 + 5 = -4. (-3, 32): The turning point is where dy/dx = 0, at x = 3, not -3. (6, 5): That is a point on the curve at x = 6, not the turning point.
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