Do you think the answer is C.147?
180-132+x-6x+12=0
48+x-6x+12=0
48-5x+12=0
60-5x=0
-5x=-60
x=12
Step-by-step explanation:
x in (-oo:+oo)
1/7-(3*((3/7)*x-(2/7))) = 0
1/7-3*((3/7)*x-2/7) = 0
1/7-3*(3/7*x-2/7) = 0
(-3*7*(3/7*x-2/7))/7+1/7 = 0
1-3*7*(3/7*x-2/7) = 0
7-9*x = 0
(7-9*x)/7 = 0
(7-9*x)/7 = 0 // * 7
7-9*x = 0
7-9*x = 0 // - 7
-9*x = -7 // : -9
x = -7/(-9)
x = 7/9
x = 7/9
Part a: Option D 18 feet per second
Part b: increasing
Solution:
Height 
Part a: To find the average rate of change for h(t) between t = 0 and t = 2.
Substitute t = 0 in h(t).

h(0) = 3
Substitute t = 2 in h(t).
h(2) = 39
Average rate of change formula:

Here, a = 0 and b = 2.



= 18
Average rate of change = 18 feet per second
Option D is the correct answer.
Part b:
This means height of the ball is increasing for 0 < x < 2.