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15 votes
15 votes
I’ve asked so many people for help and i still got it wrong please help!

consider: f(x) = - 5x2 - 10x + 6

Find the y-intercept, the equation of the axis of symmetry, and the x-coordinate of the
vertex
b. Make a table of values that includes the vertex and graph the function

User Dablak
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3.0k points

1 Answer

19 votes
19 votes

Answer:

Below

Explanation:

Use quadratic formula with a = -5 b = -10 c = 6

to find the zeroes x = -1 + sqrt(55) / 5 and -1 - sqrt(55)/5

the vertex is exactly between these two x values (due to symmetry)

add together and divide by two to get the x value of the vertex:

x = -1 use this value in the equation to get the y coordinate of the vertex = 11 vertex = -1,11

Axis of symmetry is the x value of the vertex x = -1

y intercept occurs when x = 0 plug that into the equation to find y = 6

Here is the graph:

I’ve asked so many people for help and i still got it wrong please help! consider-example-1
User Willbill
by
3.1k points