SOLUTION: I need to find the intercepts of the graph of the function for this problem s(p)= 4p2-3p-7

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Question 534169: I need to find the intercepts of the graph of the function for this problem
s(p)= 4p2-3p-7
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
We can factor the equation, setting s(p) = 0.
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(4p-7)(p+1) = 0
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Check using FOIL.
4p^2 +4p -7p - 7 = 4p^2 -3p-7
Correct.
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p +1 = 0
p = -1
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4p-7 = 0
4p = 7
p = 7/4
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+graph%28500%2C500%2C-3%2C3%2C-10%2C10%2C4%2Ax%5E2-3%2Ax-7%29+
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We can see the vertex of the parabola above. But what is the ordered pair (p, s(p))?
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To find the vertex, begin by finding the axis of symmetry.
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p = -b/2a defines the axis of symmetry
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p = -(-3)/2(4) = 3/8 = 0.375
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Then substitute that value and solve for 's(p)'.
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4(3/8)^2 -3(3/8) -7 = -121/16 = -7.5625
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So the vertex is (0.375, -7.5625).