Answer: hard to tell but I think D is correct (−∞,10],{y| y ≤ 10}
Step-by-step explanation:
Range:
(−∞,10] or {y| y ≤ 10}
because there is a vertex at (0, 10)
(found this by using -b/2a giving us 0 for x coord and plugging in 0 to 10-x² giving us (0, 10)
Then understanding since -x² is negative, the parabola goes down. And we know that the range is anything less or equal to 10
