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:
Stacy made £25.2 from the 18 loaves of bread. So She made £5.20 as a profit.
Step-by-step explanation:
18 loaves of bread × £1.4 = £25.2 Round it up = £25
£25.20 - £20 = £5.20 Round it up = £5
Stacy Made about £5 as profit.
Answer:
see explanation
Step-by-step explanation:
The excluded values are any values of x that make the function undefined
Given

The denominator of the rational function cannot be zero as this would make it undefined. Equating the denominator to zero and solving gives the values that x cannot be.
(x + 4)(x - 2)(x - 5) = 0
Equate each factor to zero and solve for x
x + 4 = 0 ⇒ x = - 4
x - 2 = 0 ⇒ x = 2
x - 5 = 0 ⇒ x = 5
x = - 4, x = 2, x = 5 are the excluded values
The length of the rectangle is 60 feet and the width of the rectangle is 45 feet.
<h3>What is the area of the rectangle?</h3>
Let L be the length and W be the width of the rectangle.
Then the area of the rectangle will be
Area of the rectangle = L×W square units
A farmer’s rectangular pen has an area of 2,700 square feet, and the width is 15 feet shorter than the length.
L = W + 15
Then we have
2700 = W(W + 15)
W² + 15W - 2700 = 0
W² + 60W - 45W - 2700 = 0
(W + 60)(W - 45) = 0
W = 45, -60
Then the dimension of the rectangle will be
W = 45 feet
L = W + 15
L = 45 + 15
L = 60 feet
More about the area of the rectangle link is given below.
brainly.com/question/20693059
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