A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 4 years ago
Two cars leave from the same point (A) and travel along a straight road, which are at angle of 78° to each other. If their speeds are 120 km/h (truck) and 90 km/h (car) respectively, how far apart will they be after one half hour?
a. Draw a diagram.
b. Distance = speed x time
anonymous
 4 years ago
Two cars leave from the same point (A) and travel along a straight road, which are at angle of 78° to each other. If their speeds are 120 km/h (truck) and 90 km/h (car) respectively, how far apart will they be after one half hour? a. Draw a diagram. b. Distance = speed x time

This Question is Closed

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Distance traveled by car 1 = 60 Distance traveled by car 2 = 45 Now, we can use the rule of cosines, \( \sqrt{60^2 +45^2 2\times\cos 78^\circ\times60 \times 45 } = \cdots \)

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1328198470260:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0How did you get the distance? Since you both have different answers?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Law of cosines:\[c ^{2} = a ^{2} + b ^{2}  2abcos(\gamma)\] So: sqrt(60^2 + 30^2  2*30*60*cos(78)) = ~61

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0why 30 lauriy? Am I missing something ...

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Sorry not 30 but 45... sqrt(60^2 + 45^2  2*45*60*cos(78)) = ~67.1

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Uhm I still don't understand how the distance go calculated? Like, how did you get 60, and 45? what steps? I understand the cos law, Thanks

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0120km/h means 120 in 1 hour. So if he only has half an hour, he will do 60 km.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Oh wow! LOL, that makes sense! Thanks a bunch!
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.