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Question 440299: Find an equation of the tangent line to the parabola y=2x^2 at the point (-1,2), and find the x-intercept of the line.
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Find an equation of the tangent line to the parabola y=2x^2 at the point (-1,2), and find the x-intercept of the line.
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y = 2x^2
y' = 4x
At x = -1, slope y' = -4
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y = mx + b
2 = -4*(-1) + b
b = -2
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Ooh, x-int
y = -4x -2 is the eqn of the tangent line
0 = -4x - 2
x = -1/2 is the x-intercetp
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