<span><span>PART A) the initial value of the function is 150 at 0 weeks, that means that there are still 150 songs to be downloaded at the beginning.
</span> The rate of change is -30 songs each week, that is because the amount of songs left to be downloaded decrease by 30 each week.</span>
<span><span>PART B:
</span><span> lets use 2 points of the graph p1(0, 150), p2(1, 120)
calculate the slope:
m = (y2- y1)/(x2 - x1) = (120 - 150)/(1 - 0)
m = -30
and now use line equation in form point-slope:
y - y1 = m(x - x1)
y - 150 = -30(x - 0)
y = -30x + 150</span></span>
(x)1100+(y)113 x depends on the amount of computers is sold so x will change. y will be the amount of hard drives sold and then you add the total amount together.
Double angle identity for sine:


Factorize the left side.

Pythagorean identity:


so that

According to Wikipedia: "<span>In mathematics, a function
is a relation between a set of inputs and a set of permissible outputs
with the property that each input is related to exactly one output."
So based of this we need to look for a set where one of the x values or the y values is the same, and the other number is different.
Answer:
B.
(1,4) and (1,1) both have the same x, but different y!
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