Answer: $19.6
Step-by-step explanation:
Linear function: f(x)=mx+c
, where m= rate of change in f(x) with respect to x.
c = Initial value.
Let c = Initial value of card , m= Charge per minute
x= Number of minutes calling time.
Then, 25.06= 38m+c (i)
21.03=69m+c (ii)
Eliminate (ii) from (i)

Put m in (i) , we get

i.e. f(x)=-0.13x+30
if x=80 then
f(80)= -0.13(80)+30
=-10.4+30
=19.6
Hence, the remaining credit after 80 minutes of calls = $19.6
Answer:
21
Step-by-step explanation:
lol
Observe the sequences below. I. 3, 6, 9, 12, ... II. 3, 9, 27, 81, III. 2, 4, 8, 16, ... IV. 3, 5, 7, 9, Which of these are geom
Sholpan [36]
Observe the sequences below. I. 3, 6, 9, 12, ... II. 3, 9, 27, 81, III. 2, 4, 8, 16, ... IV. 3, 5, 7, 9, Which of these are geometric sequences? III only O Il and me II and IV O I and
q(x)= x 2 −6x+9 x 2 −8x+15 q, left parenthesis, x, right parenthesis, equals, start fraction, x, squared, minus, 8, x, plus, 1
AURORKA [14]
According to the theory of <em>rational</em> functions, there are no <em>vertical</em> asymptotes at the <em>rational</em> function evaluated at x = 3.
<h3>What is the behavior of a functions close to one its vertical asymptotes?</h3>
Herein we know that the <em>rational</em> function is q(x) = (x² - 6 · x + 9) / (x² - 8 · x + 15), there are <em>vertical</em> asymptotes for values of x such that the denominator becomes zero. First, we factor both numerator and denominator of the equation to see <em>evitable</em> and <em>non-evitable</em> discontinuities:
q(x) = (x² - 6 · x + 9) / (x² - 8 · x + 15)
q(x) = [(x - 3)²] / [(x - 3) · (x - 5)]
q(x) = (x - 3) / (x - 5)
There are one <em>evitable</em> discontinuity and one <em>non-evitable</em> discontinuity. According to the theory of <em>rational</em> functions, there are no <em>vertical</em> asymptotes at the <em>rational</em> function evaluated at x = 3.
To learn more on rational functions: brainly.com/question/27914791
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