Question

Use the function f(x) to answer the questions:

f(x) = 2x2 − x − 10

Part A: What are the x-intercepts of the graph of f(x)? Show your work. (2 points)

Part B: Is the vertex of the graph of f(x) going to be a maximum or a minimum? What are the coordinates of the vertex? Justify your answers and show your work. (3 points)

Part C: What are the steps you would use to graph f(x)? Justify that you can use the answers obtained in Part A and Part B to draw the graph. (5 points)

Answer 1

Answer: hes right

Step-by-step explanation: i took the test

Answer 2

Part A: (2x−5)(x+2)

Part B: (5/2,0) and (-2,0)

Part C: The graph of f(x) has both "ends" of the graph pointing upward. You can describe this as heading toward infinity.

Part D: To graph function we can use x-intercepts and "ends" to sketch.In order to graph better use one more point of parabola that you can find as the average of x-intercepts: (-2+5/2)/2 =1/4.This is just x coordinate and you need to plug in 1/4 in the f(x) and find y coordinate -10 1/8. You can use y-intercept (0,-10) as well to graph.

Explanation:

2x^2-3x-5=y

(2x-5)(x+1)=y

(2x-5)(x+1)=0

2x-5=0

2x=5

x=2.5

x+1=0

x=-1

you have an even degree (2) and a positive coefficient (2)

therefore as x---> -∞, f(x)----> +∞

also, as x----> +∞, f(x)----> +∞

also notice that this is a parabola that opens upwards so both "ends" approach positive infinity

plot the x-intercepts, find the vertex using h=-b/2a and substituting this value into the equation to find k and make a table of values to graph the parabola unless you only want a rough sketch of the graph-you know the x-intercepts and you found the vertex using h=-b/2a

Explanation: