Find the value of csc Θ if cos Θ = - 3/5 180° ≤ Θ < 270°

csc =

csc Θ = - 5/4

Step-by-step explanation:

Consider a coordinate plane. As the range is from 180 to 270, we find that the triangle to be created should be in the 3rd quadrant.

cos Θ = - 3/5

5 ---> hypotenuse

- 3 --> adjacent side

Θ = angle is between the respective sides

We have to find the length of the remaining side, which would be the following:

- √5^2 - (-3)^2 = - √25 - 9

                        = - √16

                        = - 4

Remember csc Θ = Hypotenuse/Opposite =  5/-4 = - 5/4

  or  

sin y = 7/q

7 is the opposite side length, q is the hypotenuse

tan y = 7/r

7 is the opposite side length, r is the adjacent side length

using sohcahtoa ^^^^

cos y = adjacent/hypotenuse

cos y = r/q