Answer: A) y=25, B) y=10 C) y=-5 D)y=-20
Step-by-step explanation:
So whenever you have a question like this just plug in the values.
A) x=0
y= -3x+25 will now turn into y=0+25, so y=25
B) x=5
y= -3x+25 is now y= -15 +25, so y=10
C) x=10
y= -3x+25 is now y= -30+25, so y=-5
D) x=15
y=-3x+25 is now y= -45+25, so y=-20
Let us check the transformations. The first step is regarding the argument of the function, the -2x part. So, first of all, the minus sign implies that the function is reflected along the y-axis since f(x) is replaced with f(-x). However, cosx is symmetric along that axis so there is no change on the graph. Also, the 2 factor means that the function is compressed along the x-axis, since now f(2) corresponds to f(1) etc. (if we substitute 1 in the cos(2x), it is as if substituting 2 in the origninal function cosx). Finally, we have that the factor 3 in front of cos, implies that the function is dilated along the y-axis; the highs become 3 times higher and the lows 3 times low.
Answer:
x = -1/4
Step-by-step explanation:
= 1/3
= 
4x = -1
x = -1/4
Answer:
- The first graph (see figure attached)
Explanation:
<u>1. Number of pages read by Robert</u>
Set a function for the number of pages read by Robert, taking into account that this is an arithmetic sequence, whose first term is 30, and the common difference is 20:

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first day next days
<u>2. Number of pages read by Tony:</u>
The arithmetic sequence that represents the number of pages read by Tony has first term 40, and common difference 14:

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first day next days
<u>3. Find the numbers of pages read by Tony in terms of the number of pages read by Robert.</u>
To do that, you must clear n from both equations and equal the two expressions obtained:
From R(n) = 30 + 20 (n - 1):
- R(n) = 30 + 20n - 20
- R(n) = 10 + 20n
- n = [R(n) - 10]/20
You can change R(n) to r:
From T(n) = 40 + 15 (n - 1)
Change T(n) to t
Equal both expressions:
- (r - 10) / 20 = (t - 25)/15
Solve for t:
Find some points of the equation t = 0.75r - 17.5 to compare with the points of the graph:
- r = 0 ⇒ t = 17.5, that means that the line intercepts the vertical axis at 17.5. The only graph that matches this is the first graph
Find other point:
- r = 30 ⇒ t = 0.75(30) + 17.5 = 40.Thus, the graph must contain the point (30, 40), which the first graph does.