Answers: -6 and -4
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Explanation:
Refer to the drawing below. Locate 5 on the y axis. Draw a horizontal line extending as far as you can to the left and right.
This horizontal line crosses the parabola in two locations. From those two locations, drop a vertical line straight down until you reach the x axis. You should reach x = -4 and x = -6
This shows that f(-4) = 5 and f(-6) = 5.
Phrased another way: the points (-4,5) and (-6,5) are on the parabola.
