A rock was thrown upward with an initial velocity of 24 feet per second. The rock’s height t seconds after it was thrown upward is given by the function f(x)=−16x2+24x+4755
f
(
x
)
=
−
16
x
2
+
24
x
+
4755
. Four students were trying to guess how long it would take the rock to reach the ground: Kelly guessed that it would take 15 seconds, David guessed 18 seconds, Shelly guessed 20 seconds, and Dan guessed 25 seconds. Who had the best guess?

Since opening night, attendance at play a has increased steadily, while attendance at play b first rose and then fell. equations modeling the daily attendance y at each play are shown below, where x is the number of days since opening night. on what day(s) was the attendance the same at both plays? what was the attendance? play a: y = 8x + 191 play b: y = -x^2 + 26x + 126 a. the attendance was never the same at both plays. b. the attendance was the same on day 5. the attendance was 231 at both plays on that day. c. the attendance was the same on day 13. the attendance was 295 at both plays on that day. d. the attendance was the same on days 5 and 13. the attendance at both plays on those days was 231 and 295 respectively.