D: 89 is the prime number.
Answer: y = 7.5
Step-by-step explanation:
Suppose that y varies directly with x
That is, y∝x
Convert y∝x to a full equation by introducing a constant k to the right hand side.
Therefore, y = kx
Given that y = 10 and x = 20
Substitute y and x in the equation above. We have;
10 = k(20)
10 = 20k
20k = 10
k = 10/20
k = 0.5
Since k = 0.5, the equation y = kx becomes y = 0.5x
Now, to find y if x = 15, substitute x in equation y = 0.5x
Therefore, y = 0.5(15)
y = 7.5
Using geometric sequence concepts, it is found that:
a) The rule is:
.
b) An exponential relationship exists between the two variables.
<h3>What is a geometric sequence?</h3>
A geometric sequence is a sequence in which the result of the division of consecutive terms is always the same, called common ratio q.
The nth term of a geometric sequence is given by:

In which
is the first term.
A geometric sequence represents an exponential relationship between the variables.
In this problem, considering that the first-place finisher wins half of $1.500.000 in total prize money, and each finisher earns half of the one who finished above, the first term and the common ratio are given by:
.
Hence the nth term of the sequence is given by:

More can be learned about geometric sequence concepts at brainly.com/question/11847927
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D, hope this is right! :)
Answer:
x^2-4x+<u>4</u>=(<u>x-2</u>)^2
Step-by-step explanation:
Have fun ✌️:)