
William W. answered 05/10/23
Experienced Tutor and Retired Engineer
−5tan θ − 13 = 4tan θ − 6
Add 5tanθ to both sides and add 6 to both sides to get:
-7 = 9tanθ
Divide both sides by 9 to get:
tanθ = -7/9
Take tan-1 of both sides to get:
tan-1(tanθ) = tan-1(-7/9)
θ = tan-1(-7/9)
Use you calculator to get:
θ = -37.875° or (in radians), θ = -0.661 radians
Since tan repeats every 180° (or π radians), you can also say θ = 142.125° or, generally, θ = 142.125° + 180°k where "k" is any integer. Or, in radians, θ = 2.481 radians + πk where "k" is any integer