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I KNOW IT'S A LOT BUT PLEASE HELP ME PLEASE I'VE TRIED FOR DAYS BUT DONT UNDERSTAND Step 1: For each given function below, make an XY table and plug in values for X (you make up the values). Step 2: Plug in values for each X into the equation to find Y values. Step 3: Plot the points in the table. TWO GRAPHS ONE y = -x2 OTHER y = x2 − 4 Then, once you have graphed both lines, use the coordinates of the vertex of each parabola and the Text Editor to explain whether the vertex is a maximum or minimum point of the graph, give the maximum or minimum value of the function, and describe the line of symmetry.

I KNOW IT'S A LOT BUT PLEASE HELP ME PLEASE I'VE TRIED FOR DAYS BUT DONT UNDERSTAND-example-1

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Answer: Take it one step at a time. The chart should have x values close to 0, both positive and negative. You get the y-values by substituting for x and working out the calculation.

Explanation:

chart for y = -x² Remember you are squaring the (x) then multiply × -1 so all y-values are negative numbers.

x | y

-2 -4

-1 -1

0 0

1 -1

2 - 4

Plot those points on the graph, draw the parabola. It should look like the first graph attached. Since the vertex of the parabola is at the top, it is a maximum.

The parabola is a mirror image on either side of the y-axis, so that is the line of symmetry

Chart for y = x² –4 . figure x² first, then subtract 4

x . | . y

-2 0 . +4-2=0

-1 -3 +1 - 4 = -3

0 -4

1 -3

2 0

3 1 9 - 4 = 5

Your graph should look like the second (green) attached graph

I hope this is enough help for now.

I KNOW IT'S A LOT BUT PLEASE HELP ME PLEASE I'VE TRIED FOR DAYS BUT DONT UNDERSTAND-example-1
I KNOW IT'S A LOT BUT PLEASE HELP ME PLEASE I'VE TRIED FOR DAYS BUT DONT UNDERSTAND-example-2
User Nan Xiao
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