## katherinekc 2 years ago Convert the radian measure to degree measure. Use the value of π found on a calculator and round answers to two decimal places. 9pi/4

1. Schrodinger

Just curious, do you have your unit circle values for radians memorized, e.g. pi/6, pi/4, pi/3?

2. katherinekc

not yet.. im working on it

3. irkiz

are you using a scientific calculator?

4. irkiz

type in 9pi/4 in radian mode. press 2nd function press the (change degree mode) button till it goes to degree and the conversion is done

5. katherinekc

these are the answer choices.. A. 200π° B. 405° C. 160° D. 324°

6. Schrodinger

No problem. Okay, so let's put the value 9pi/4 into a whole number based on that. So, if 8pi/4 is equal to 2pi, 9pi/4 must be equal to 2pi plus pi/4, right?

7. katherinekc

Yes

8. Schrodinger

2pi is equal to 360 degrees, and pi/4 is equal to how many degrees, if pi is the angle of a semicircle, or 180 degrees?

9. katherinekc

would it be 160 then

10. katherinekc

?

11. Schrodinger

Back, sorry. Sorry, but I don't believe so. If you divide 180/4, (because pi is 180), what do you get?

12. katherinekc

45

13. Schrodinger

Yup. So, adding together 2pi and pi/4, what would be your sum in degrees?

14. katherinekc

hm..im not sure if it did it right..

15. katherinekc

let me see.. hmm

16. katherinekc

im kinda comfusing myself..

17. katherinekc

is it 405?

18. Schrodinger

Back. Yeah, exactly.

19. katherinekc

okay, now i get it!! i know the steps..thank you!!

20. Schrodinger

you could also do the same as others were saying by using your calculator to converts, but it's good to know how to do it with radians because of their usefulness later on. Just to make sure, do you know how to do it on a calculator, like those dudes were saying?

21. katherinekc

kinda.. im alil slow on it but i kinda understand