SOLUTION: Find the x and y intercepts {{{ P(x) = x^3+4x^2-x-4 }}}

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Question 475560: Find the x and y intercepts
+P%28x%29+=+x%5E3%2B4x%5E2-x-4+
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
+P%28x%29+=+x%5E3%2B4x%5E2-x-4+
Factor this by grouping
P(x) = x^3 - x + 4x^2 - 4
P(x) = (x^3 - x) + (4x^2 - 4)
factor
P(x) = x(x^2 - 1) + 4(x^2 - 1)
Factor out (x^2-1)
P(x) = (x^2 - 1)(x + 4)
x^2 = 1
x = sqrt%281%29
x = 1
x = -1
and
x = -4
:
x intercepts: -4, -1, +1
:
Find the y intercept, occurs when x=0
y = x^3 + 4x^2 - x - 4
y = 0^3 + 4(0)^2 - 0 - 4
y = -4 is the y intercept
:
:
graphically
+graph%28+300%2C+200%2C+-6%2C+6%2C+-10%2C+10%2C+x%5E3%2B4x%5E2-x-4++%29+