Answer:
5 hours
Step-by-step explanation:
Time taken for trip : t + 1
Time taken for return : t
Avg. speed (trip) : 256 km/h
Avg. speed (return) : 320 km/h
The distances covered on both trips are equal.
⇒ Distance (trip) = Distance (return)
⇒ Speed (trip) × time (trip) = Speed (return) × time (return)
⇒ (256)(t + 1) = (320)(t)
⇒ 256t + 256 = 320t
⇒ 64t = 256
⇒ t = 4 hours
<u>Time (trip)</u> = t + 1 = 4 + 1 = 5 hours
Answer:
Step-by-step explanation:
if you can pick any numbers you want then:
rational could be: 0.25 or 1/4
irrational could be: 2/7
Answer:
4/5 = 8/10
Step-by-step explanation:
x/5 = 8/10
x = 8/10 × 5
x = 4
<h3>
Answer: cos(76)</h3>
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Explanation:
The original expression is of the pattern cos cos + sin sin. This pattern matches the second identity in the hint. Specifically, we'll say the following:
cos(A - B) = cos(A)cos(B) + sin(A)sin(B)
cos(A)cos(B) + sin(A)sin(B) = cos(A - B)
cos(94)cos(18) + sin(94)sin(18) = cos(94 - 18)
cos(94)cos(18) + sin(94)sin(18) = cos(76)
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We can verify this by use of a calculator. Make sure your calculator is in degree mode.
- cos(94)cos(18) + sin(94)sin(18) = 0.24192
- cos(76) = 0.24192
Both expressions give the same decimal approximation, so this helps confirm the two expressions are equal. You could also use the idea that if x = y, then x-y = 0. Through this method, you'll subtract the left and right hand sides and you should get (very close to) zero.
