Answer:
6400
Step-by-step explanation:
Given the profit function ;
P(c) = –20c2 + 320c + 5,120
The maximum value is given by :
f(h) ; where, h = - b /2a
From P(C) ; a = - 20 ; b = 320
h = - b / 2a = - 320 / 2(-20) = - 320 / 40 = 8
c = h
P(8) = –20(8)² + 320(8) + 5,120
P(8) = - 1280 + 2560 + 5120
= 6400
What you can put is an obtuse 108 degrees
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Answer:
20 or 40 or 50
(there are many others)
Step-by-step explanation:
A counterexample is an example that shows the statement is not true. The statement in this question is that if a number is a multiple of 10 (10, 20, 30, 40, 50, 60...) then it is a multiple of 30. Some numbers are, like 60 and 90, but not all numbers. So for example (counterexample) 20 is a multiple of 10 but NOT a multiple of 30.
40 is a multiple of 10, but NOT a multople of 30.
50 is a multiple of 10, but NOT a multiple of 30.
Let the number of minutes be = x.
Cost per minute = 11 cents = 0.11
Phone Bill = Monthly fee + 0.11* x
Substituting from the question
20.82 = 3 + 0.11x
3 + 0.11x = 20.82
0.11x = 20.82 - 3
0.11x = 17.82
x = 17.82/0.11
x = 162
<span>Lamar was billed for 162 minutes.</span>