SOLUTION: Please help me write a polynomial with the following characteristics degree=3 real coefficients zeros at x=2 and x=-5=5i y intercept at (0,300)

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Question 1191876: Please help me write a polynomial with the following characteristics
degree=3
real coefficients
zeros at x=2 and x=-5=5i
y intercept at (0,300)
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
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degree=3
real coefficients
zeros at x=2 and x=-5%2B-+5i
y intercept at (0,300)
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y=a%28x-2%29%28x-%28-5-5i%29%29%28x-%28-5%2B5i%29%29

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y=a%28x-2%29%28x%2B5%2B5i%29%28x%2B5-5i%29
y=a%28x-2%29%28%28x%2B5%29%2B5i%29%28%28x%2B5%29-5i%29
a%28x-2%29%28%28x%2B5%29%5E2-%285i%29%5E2%29
a%28x-2%29%28x%5E2%2B10x%2B25-%2825%29%28-1%29%29
a%28x-2%29%28x%5E2%2B10x%2B50%29
a%28x%5E3%2B10x%5E2%2B50x-2x%5E2-20x-100%29
a%28x%5E3%2B8x%5E2%2B30x-100%29

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The point or x-intercept (0,300),
a%280%2B0%2B0-100%29=300 when substitute for x;
-100a=300
a=-3
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highlight_green%28-3%28x%5E3%2B8x%5E2%2B30x-100%29%29
You can continue multiplying that fully if you need to.