Question

The Secant of angle A is -5/4. a) What quadrants could angle A be in? b) Determine the measure(s) of angle A

Answer 1

a) 2nd and 3rd quadrant

b) 143.13° and 36.87°

Explanation:

Secant A = 1/cosecant A

sec A = 1/cosA

If Sec A = -5/4

Cos A = 1/(-5/4)

CosA = -4/5

Since cos A is a negative values, hence the angle A will be in the 2nd and 3rd quadrant

b) If CosA = -4/5

A = arccos(-0.8)

A = 143.13

A = 180 - 143.13

A = 36.87

Hence the measures of angle A are 143.13° and 36.87°