<span>Replace tan θ with sin θ/cos θ
= sin²θ/cos θ + cos θ
Now multiply the right-hand side by cos θ/cos θ to get the same denominator:
= sin²θ/cos θ + cos²θ/cos θ
= (sin²θ + cos²θ)/cos θ
The numerator is equivalent to 1:
= 1 / cos θ
= sec θ</span>
Answer:
porfavor en español pls para yo poder resolverlo
it's B why they need me to write something long the answer is ez B
Step-by-step explanation:
it f common sense
Answer:
20,365.7 seconds
Step-by-step explanation:
First, we need to know how to convert yards to miles, as the question is in miles. We know that 1 mile is equivalent to 1760 yards. So we have:
1 mi = 1760 yards
If we multiply both sides by 81:
81 mi = 142,560 yards
And we know that the sprinter needs 8 second to run 56 yards:
8 s = 56 yards
If we divide both sides by 56 we get the time he needs for 1 yard:
8/56 s = 56/56 yards
1/7 s = 1 yard
So, takes him 1/7 seconds to run one yard. At this rate he runs 142,560 yards in:
(1/7) * 142,560 = 20,365.7
So, he needs 20,365.7 seconds to run 81 miles (142,560 yards)
