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Question 175040: 2x=-(y+2)^2
Answer by Mathtut(3670)   (Show Source):
You can put this solution on YOUR website!  this is a horizontal parabola. horizontal parabola formula is (h,k) is the vertex and 4p is the width of the parabola
there is no question so perhaps you would like a graph
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Graphing Parabolas that Open Horizontally
Methods
1) If the only variable that is squared is y, then Complete the Square on the y terms and move the x term and the constant term to the other side to put the equation into the form :
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we already have a completed square and we have written this in the proper form
2) Plot the point (h,k) . This is the vertex of the Parabola.
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h=0 and k=-2 so vertex is at (0,-2)
3) Compute the value of p from the multiplier on ( x - h ) . Move to the right this distance from the vertexif p is positive. Move to the left from the vertex if p is negative. This is the location of the focus. The parabola will “wrap” around the focus as it goes through the vertex.
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our multiplier is -2 so set 4p=-2--->p=-1/2 since p is negative move a distance of 1/2 to the left of the vertex for the focus. meaning the focus is at (-1/2,-2)
4) The width of the openning at the focus is equal to 4p. Plot two points, 2p units above and below the focus to get two more points on the Parabola. Draw a smooth curve through the vertex and these two points.
the width distance is 2 therefore 2p=1 so plot one point 1 unit above the focus and the other 1 unit below the focus. meaning we have points at (-1/2,-1) and (-1/2,-3).
5) Two points where the parabola crosses the y-axis can be found by setting x = 0 and solving the quadratic equation for the two y-intercepts. Only one or no y-intercepts might exist.
y+2=0 so y intercept is at (0,-2)
6) The single point where the parabola crosses the x-axis can be found by setting y = 0 and solving the linear equation for the x-intercept. There will always be a single x-intercept.
when y=0 (0+2)squared=-2x
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4=-2x--->x=-2...so x intercept is at (-2,0)
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you should be able to graph this as the parabola opens to the left
only 1/2 of the graph is shown here....the upper half
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