A. Not a function since we have the points (-1,0) and (-1,3). The x value repeats while the y values are different. Plugging in x = -1 leads to multiple outputs, which shows we don't have a function. To get a better visual, you can plot the points. You'll see that the points form a vertical line. Therefore, this graph fails the vertical line test.
B. This is a function. All of the x values are different. The points, when graphed, pass the vertical line test. In other words, its impossible to draw a vertical line through any two points on the graph. Any x input here leads to exactly one y output.
C. This is not a function. Like choice A, we have repeated x values. In this case we have (4,6) and (4,7). The x value x = 4 repeats itself leading to multiple outputs y = 6 and y = 7
D. This is also not a function. The x value x = 0 repeats itself. The graph fails the vertical line test.
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Answer: Choice B
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Answer: 81.2
Step-by-step explanation:
h(t) = -5t² + 40t + 1.2
h(4) = -5(4)² + 40(4) + 1.2 We plug 4 seconds as t, and solve h(4)
h(4) = -80 + 160 + 1.2
h(4) = 80 + 1.2
h(4) = 81.2
There would be an open circle on positive 12 with the arrow moving to the right.
