## rebeccaskell94 3 years ago @SmoothMath I need your help D: Use △DEF, shown below, to answer the question that follows. http://learn.flvs.net/webdav/assessment_images/educator_geometry_v14/pool_Geom_3641_0402_02/0402_G2_Q3.gif What is the value of x rounded to the nearest hundredth?

1. SmoothMath

What have you tried so far?

2. mathslover

|dw:1341504473383:dw|

3. SmoothMath

This is very similar to the kind of problem I taught you before.

Well I looked at the triangle and saw that like EF is opposite and DE is adjacent sooo I use tan?

5. SmoothMath

Very good. Keep going. Use tangent to set up the equation.

6. mathslover

soa cah toa .. tan (theta)= opposite / adjacent .. good u r going right best of luck

7. SmoothMath

soh cah toa*

SmoothMath help me

9. SmoothMath

Sorry, Becca is cuter.

:3> xD thanks Okay, um Tan(45) = x/55 ?

x= 2,475

12. SmoothMath

Looks good. Solve for x and then round to the nearest hundredth like they ask.

13. SmoothMath

Oh wait. One problem with your equation. The angle isn't 45.

lol derp. 49 Tan(49) = x/55 x= 2,695

or just 2700

16. SmoothMath

I don't know what you did, but 2,695 is super super off.

D: I thought it was 49 x 55 to find out x to then divide it and then make it like...right =2695/55 = 49

18. SmoothMath

TANGENT of 49... super different from 49. Use your calculator to find out what tan(49) is. Make sure you're in degrees and not radians.

19. SmoothMath

tan(49) = x/55 Just solve for x, then let your calculator do the trig function for you.

my calculator doesn't do anything but x/55

21. SmoothMath

It really doesn't have sin cos tan buttons on it? You'll need to use a different calculator then, or else use google or alpha.

This is what I use http://web2.0calc.com/

Or is it just the 1.15 thing

ohhh like tan(49) = 1.15/55 ?

25. SmoothMath

Far left, below pi, you'll see the buttons sin, cos, and tan. Those are your trig functions. To do this one, click tan, then 49, then ). Should look like this: I've boxed the trig function buttons in blue and the way to switch between degrees and radian modes in green.

26. SmoothMath

Becca, please don't forget how to do simple algebra. tan(49) = x/55 How do you solve for x?

49/1 • x/55? ... My brain...it's dying. :(

28. SmoothMath

multiply both sides by 55. -_-

-__- dollface 49 • 55 and x/55 • 55?

30. SmoothMath

not 49*55. tan(49)*55

31. SmoothMath

and what is x/55 * 55?

1?

33. SmoothMath

oh my goodness. Becca, can you solve this equation for me? 4 = x/2

8

35. SmoothMath

Same dang thing here. tan(49) = x/55

36. Wolfboy

55*49.........

37. SmoothMath

Wrong, wolfboy.

Its not just 55*49 D: he said it's tan(49) :(

39. SmoothMath

55* tan(49)

40. Wolfboy

I. Thought sooo......hmmmmmm

41. Wolfboy

Sooo we need the formula for tan or a couculater

63.27?

43. SmoothMath

Yes. Let me just show you the last 2 steps. You got as far as tan(49) = x/55 multiply both sides by 55. That's basic algebra, solving for x. 55*tan(49) = x tan of 49, when you put in your calculator is 1.15036841 and 55*(1.15036841) = 63.2702625 then, of course you round to the nearest hundredth.

Thank you dollface :D Sorry if I frustrated you :c

45. SmoothMath

You didn't, cutesie buttons. I'm happy to help. =)