SOLUTION: find the intercepts and vertex y=-x^2-4x find intercepst x^3-2x^2-9x=18=0

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Question 65282: find the intercepts and vertex
y=-x^2-4x
find intercepst
x^3-2x^2-9x=18=0
Answer by amran(4) About Me  (Show Source):
You can put this solution on YOUR website!
find the intercepts and vertex for +y=-x%5E2-4x+
When x=0, y=0.
When y=0, +-x%5E2-4x+=+0+
+x%5E2%2B4x+=+0+
+x%28x%2B4%29+=+0+
x = 0 or x = -4.
Hence the intercept points are (0,0) and (-4,0)
+y=-x%5E2-4x+
+-y+=+x%5E2+%2B+4x+
+-y+%2B+4+=+x%5E2+%2B+4x+%2B+4+
+-%28y-4%29+=+%28x%2B2%29%5E2+
Hence the vertex is (-2,4)


find intercept for x^3-2x^2-9x=18=0
+x%5E3-2x%5E2-9x%2B18+=+0+
+x%5E2%28x-2%29-9%28x-2%29+=+0+
+%28x-2%29%28x%5E2-9%29+=+0+
+%28x-2%29%28x-3%29%28x%2B3%29+=+0+
x = 2 , 3 or -3
Hence the intercepts are (2,0) , (3,0) and (-3,0)