For which interval is the function positive?

Question

For which interval is the function positive?
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A.–3 < x < –2

B.4 < x < 5

C.–2 < x < 4

D.–3 < x < 1

Answer 1

Positive means that the function value, which is represented by the y-axis in the graph, is greater than 0.  If you look at the graph you will see that it intersects the x-axis at 2 places, when x = -2 and when x = 4.  These are places where the function value is equal to 0.  The function is above the x-axis between these 2 places, so the values of x between these 2 places give you the interval where the function is positive.