## anonymous one year ago Suppose angle A=pi/4 radians and length of b=3

1. anonymous

2. anonymous

since angle a is pi/4 radians angle a is 45 degrees

3. anonymous

and angle b is 45 degrees

4. hartnn

ohh i like pi/4 angle the angles become congruent and 2 sides become equal :P

5. anonymous

:D I set up tan45=a/3

6. anonymous

and got that a=3

7. hartnn

correct

8. anonymous

since it's a 45-45-90 triangle a and b are both 3

9. hartnn

agreed

10. anonymous

so 3^2+3^2=c^2, 9+9=c^2, 18=c^2 i'm not sure if we need to get square root of 18

11. hartnn

ok, lets use a trig function then find sin A or sin B

12. anonymous

so sin(45)=3/c, c=3*sin45 which is 2.12

13. hartnn

you can keep it as $$3/ \sqrt 2$$

14. anonymous

where did we get the 3/sqrt of 2 from? lol

15. hartnn

because it is mentioned, "no decimals"

16. hartnn

sin 45 = 1/$$\sqrt 2$$ 3 sin 45 = 3/$$\sqrt 2$$

17. anonymous

sin of 45 =sqrt(2)/2..

18. hartnn

|dw:1443980994981:dw|

19. anonymous

hmm a little confused why we are multiplying by 2 :/

20. hartnn

we're braking 2 as $$\sqrt 2 \times \sqrt 2$$ if thats confusing you, you can keep the answer as $$3\sqrt 2/2$$ also

21. anonymous

so the length of a should be 3,

22. hartnn

length of a was always 3... i though we were talking about length of c

23. anonymous

Yea I'm just clarifying :)

24. anonymous

and length of c=3sqrt(2)/2?

25. anonymous

for some reason it's saying that c isn't correct

26. hartnn

try 3/ $$\sqrt 2$$ once?

27. anonymous

so since I got it wrong it gave me the same problem expect a=6

28. hartnn

oh wait! sin A = a/c c = a/ sin A = 3/ sin 45 = 3 sqrt 2 :P

29. hartnn

now it'll be 6 sqrt 2

30. hartnn

$$6\sqrt 2$$

31. anonymous

and b would just equal 6 because they are 45-45-90

32. hartnn

correct!

33. anonymous

yay :D it's right thank you

34. Mertsj

Since it is an isosceles triangle and b = 3, then a = 3 and the hypotenuse= 3sqrt2 and both A & B are pi/4 radians

35. hartnn

^^

36. anonymous

Mertsj, thank you for the information :)

37. Mertsj

yw