# Thread: How to find the measure of angle theta

1. ## How to find the measure of angle theta

Can someone explain the steps in finding angle theta using:

arctan(θ) = -2.1 and 90° < θ < 180°

Thanks!

2. Originally Posted by drpepper
Can someone explain the steps in finding angle theta using:

arctan(θ) = -2.1 and 90° < θ < 180°

Thanks!
I believe your notation is incorrect ...

$\tan{\theta} = -2.1$

solving for $\theta$ so that it ends up in quadrant II

$\theta = \arctan(-2.1) + 180$

punch the right side into your calculator

3. Oops, yeah, it was supposed to be just the tangent.

Thanks for the help!