Using the unit circle, you can visualise the secant as follows:
- Draw the vertical line passing trough (1,0)
- Extend the radius until it meets this line at point P
- The length of OP is the secant of your angle.
Since -90 means that the radius points downwards, it means that the radius is vertical as well, and thus it never meets the vertical line through (1,0).
Thus, the secant is not defined at -90.
In fact, if we switch back to the function notation, we can confirm this claim, since we have

which is undefined.
Answer:
50cm
Step-by-step explanation:
oh apdiya I just wanted to let you
Answer:
Im like 99% sure its B i had the assignment and got a 94
Step-by-step explanation:
<h3>
Answer: n+15</h3>
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Explanation:
- n = number of minutes
- cost of company X = 3n+30
- cost of company Y = 2n+15
To find out how much more company X charges, we subtract the two cost expressions
CompanyX - CompanyY = (3n+30)-(2n+15) = 3n+30-2n-15 = n+15 which is the final answer.
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An example:
Let's say you talk on the phone for n = 20 minutes.
Company X would charge you 3n+30 = 3*20+30 = 90 cents
Company Y would charge you 2n+15 = 2*20+15 = 55 cents
The difference of which is 90-55 = 35 cents.
If you plugged n = 20 into the n+15 expression we got, then n+15 = 20+15 = 35 matches up with the previous 35 cents.
This example helps confirm the answer. I'll let you try out other examples.