Parabola question (1 Viewer)

FTW

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good question.
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y=7-5x-2x^2

Hey people, I had this question while studying and I'm not exactly sure how to do it, I have a vague idea but I think some of my answers may be incorrect. If anyone knows, could you please post below.

Identify the:
Y intercept
X intercepts
Symmetrey
Vertex

Thanks.
 

lychnobity

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y=7-5x-2x^2

Hey people, I had this question while studying and I'm not exactly sure how to do it, I have a vague idea but I think some of my answers may be incorrect. If anyone knows, could you please post below.

Identify the:
Y intercept
X intercepts
Symmetrey
Vertex

Thanks.
y int, when x=0, .'. y = 7

y = (7+2x)(1-x), .'. x int (when y=0) = -7/2 or 1

Axis of symmetry = -b/2a = 5/-4 = -5/4

vertex is on the axis of symmetry, so vertex's y value is when x = -5/4. Sub this in:

y = 7 - (-5/4) - 2(-5/4)2 = 11.375

.'. vertex has coordinates (-1.25, 11.375)
 

Xcelz

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no probs, any other questions you have you can PM me if you like.
 

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