Vertical tangent lines

Question

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Find all points where vertical tangent lines exist for the graph of x²+3y²+6y = 6.

A. (-1,3)

B. (-1,3) and (-1,-3)

C. (3,-1)

D. (-3,-1) and (3,-1)

Answer 1

Complete the square for the y terms.

You have an ellipse with the major axis horizontal.

The center of the ellipse is (0, -1).

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