The point (-5,5) in on the terminal side of angle t. Find sec(t) to 2 decimal points.

Question

Been stuck on this for a while I get confused about sec. Please help!

Thanks!

Answer 1

Secant is 1/cosine

 

The point (-5,5) is at 135°

cosine 135° = -√2/2

secant 135° = -2/√2 = -√2 ≈ -1.41

Answer 2

Based on the point given, we know the reference angle is 45 degrees.  If we were to draw a vector from the point to the origin, and then use it to make a right triangle, we would get the reference angle.  however, we want the terminal angle.  The terminal angle is the angle counterclockwise from the positive x-axis.  So the terminal angle is

 

Terminal angle = 90 + 45 = 135

 

sec(135) = 1 / cos(135) = -1.41