SOLUTION: Find parametric equations for the rectangular equation: (x+2)^2 = 4(y-1)

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Question 338132: Find parametric equations for the rectangular equation: (x+2)^2 = 4(y-1)
Answer by galactus(183) About Me  (Show Source):
You can put this solution on YOUR website!
Solving this for y yields y=x%5E2%2F4%2Bx%2B2
This parabola has axis parallel to the y axis and has vertex at (-2,1)
p=1 and the focus is at (-2,2) and the directrix at (-2,0). The directrix is the x-axis.
Parametrically, it can be represented by
x%28t%29=2t-1
y%28t%29=t%5E2%2Bt%2B5%2F4
See, if we solve x for t, we get %28x%2B1%29%2F2
Sub into y and get:
%28%28x%2B1%29%2F2%29%5E2%2B%28%28x%2B1%29%2F2%29%2B5%2F4=x%5E2%2F4%2Bx%2B2