## robinkss 2 years ago if you are trying to find an angle and you only have this equation, 3x-14, how do you solve

1. theEric

Well, that's actually an expression, not an equation. An equation needs equal expressions, like$y=3x-14$I assume that the angle you want to know is on the graph of $$y=3x-14$$. Does that seem right, so far?

2. robinkss

yes

3. theEric

Alright, now, have you learned trigonometric functions yet?

4. robinkss

not yet

5. theEric

Is this a question for class, or is it your own curiosity? I might have to research another way to get the angle than I had thought of using earlier.

6. robinkss

this is homework from summer

7. theEric

And you don't know about the tangent a.k.a. $$tan$$ function?

8. robinkss

no

9. theEric

Well, I guess we might as well look at the graph.|dw:1374722124721:dw|I'm not sure which angle the question wants, but I assume it's the angle of the line measured from the x-axis and you would use the tangent function. Maybe I can find others to help us... With the tangent function, you use the equation $$tan^{-1}(m)=\theta$$ where $$m$$ is your slope and $$\theta$$ is its angle.

10. robinkss

ok

11. robinkss

nevermind

12. theEric

I would imagine you are, especially if you never used the tangent function! But I don't know any other way!

13. Hero

Alternatively you can just use a protractor and graph paper.

14. theEric

Ahhhhhh.... I seeee.... So, measuring, not calculating. I think I remember doing that before, too.

15. robinkss

oh so instead of finding y you just measure from what x is?

16. theEric

So you'll need to have grid paper, so your line is straight and your axes are perpendicular and everything is accurate. Then you can measure the line accurately. Thank you, @Hero !

17. theEric

|dw:1374722785269:dw|

18. theEric

Do you have grid paper and a protractor?

19. robinkss

ya and i think i got it thank you @theEric

20. theEric

Sweet. Just set up the protractor along the $$x$$-axis (or at least parallel to the $$x$$-axis) and have that point on the line. Good luck :)