a0a只是得一條喔,中4MATHS

7.
(a)
From the garph, the cost of a 7 minute call using Kingcom is 80 cents.
(b)
From the graph, (the y-intercpet of the straight line of Phoneshop) the value of p is 33.
(c)
From the graph, when t = 10, the cost = 103.
103 = 33 + 10q
10q = 70
q = 7
Therefore, the value of q is 7.
(d)
From the graph, the intersections of the two graphs are (1.0, 40) and (7.7, 87).
The required region is 1.0 < t < 7.7.