## anonymous one year ago given that a=25 b=43 and c=17, solve triangle abc

1. anonymous

2. campbell_st

so are they side measurements or angles measurements..?

3. anonymous

not sure thats all the question that its asking!!

4. campbell_st

so the letters in the question are all lower case..?

5. anonymous

oh ... it looks like this

6. campbell_st

ok... that makes more sense, you have been given 2 angles and 1 side

7. anonymous

oh

8. campbell_st

lets start with the easy one if angle A = 25 and angle B = 43 what is the measure of angle C..?

9. anonymous

ummmm... i know im gonna sound dumb! but im not sure :(

10. campbell_st

here is a diagram |dw:1436219098207:dw|

11. campbell_st

ok... so the angles in a triangle add to 180 degrees so C = 180 - 25 - 43 what would you say C is..?

12. anonymous

C=112

13. campbell_st

great... so you have eliminated 2 answer choices... its between A and B so do you know the law of sines...?

14. anonymous

not really

15. campbell_st

you need the law of sines to find a and b |dw:1436219276410:dw|

16. campbell_st

wow... that makes it hard to answer the question so the law of sines is uses the side and angle measures to find other sides and angles the law you'll need is $\frac{c}{\sin(C)} = \frac{a}{\sin(A)}$ have you seen that before..?

17. anonymous

yea yea... but i dont remember a thing!

18. anonymous

i dont mean to sound mean or anything ! but im on timed test and i have 5 mins left... is it possible if you can help me faster ? thank you

19. campbell_st

ok... then here is a quick and dirty method to solve the problem... there is this stuff about triangles that says the longest side is opposite the largest angle the shortest side is opposite the smallest angle the middles length side is opposite the middle angle measure so the angles in order of side are Angle C = 112 side c = 17 Angle B = 43 side b = 12,5 or 7.5 Angle A = 25 side a = 12.5 or 7.5 so using the facts about sides and angles... what side matches angle A and which side matches angle A

20. campbell_st

think about the shortest is opposite the smallest angle

21. campbell_st

this quick an dirty method eliminates the need for calculations in this question

22. anonymous

so would the answer be B ??

23. campbell_st

that would be my guess

24. anonymous

alright... thank you very much campbell_st !