<h3>
Answer: Yes</h3>
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Explanation
The ratio 8:10 simplifies to 4:5 when you divide both parts by 2.
The ratio 16:20 simplifies to 4:5 when you divide both parts by 4
Therefore the two ratios 8:10 and 16:20 are both equal 4:5, so they are equal to one another.
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Put another way,
(8 large)/(10 small) = (16 large)/(20 small)
8/10 = 16/20
8*20 = 10*16 ... cross multiply
160 = 160
We get a true equation, so the first equation is true as well.
This shows the ratios are equivalent.
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Or you could have...
(8 large)/(16 large) = (10 small)/(20 small)
8/16 = 10/20
8*20 = 16*10
160 = 160
We get the same conclusion as before.
Calculate the square root which is -7*6-(-2)*(-3) and then multiply the numbers which is -42+2*(-3) that equals -42-6 and your answer is -48
'a' is the correct answer
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.
