We'll assume this is an arbitrary triangle ABC.
A) No, the sines of two different angles can be whatever they want
B) sin(B)=cos(90-B)
Yes, that's always true. The "co" in cosine means "complementary" as in the complementary angle, which adds to 90. So the sine of an angle is the cosine of the complementary angle.
C) No, the correct identity is sin(180-B)=sin B. Supplementary angles share the same sine.
D) Just like A, different triangle angles often have different cosines.
Answer: Choice B
This is just about substitution!! 9(5)-3(5), 3 • 5 = 15
9 • 5 = 45
so Now you have, 45 - 15 = 30
Answer: y=4x-7
Step-by-step explanation:
Negative Exponent Rule:
this says that negative exponents in the numerator get moved to the denominator and become positive exponents. Negative exponents in the denominator get moved to the numerator and become positive exponents.
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Using the relation between velocity, distance and time, it is found that t = 3 hours.
<h3>What is the
relation between velocity, distance and time?</h3>
Velocity is <u>distance divided by time</u>, hence:

For this problem, the parameters are given as follows:
d = 15 miles, v = 5 mph
Hence the time in hours is found as follows:


5t = 15
t = 15/5
t = 3 hours.
More can be learned about the relation between velocity, distance and time at brainly.com/question/24316569
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