Joel L. answered 04/11/21
MS Mathematics coursework with 20+ Years of Teaching Experience
The sides of the triangle is obtained from a special triangle (30-60-90) or from Pythagorean Theorem.
or
x = 3 cos 60˚ = 1.5
y = 3 sin 60˚ = 3√3 / 2 ~ 2.6
a) answer: (1.5 km/h, 3√3 / 2 km/h)
b) located in the third quadrant
r2 =(-5)2+(-10)2
r =√35
tan θ = -10/(-5) = 2
θ = tan-1 (2)
θ = 63.43˚ (This is located on the first quadrant. We need to add 180˚)
θ = 243.43˚
Therefore, the Polar for rectangular (-5,-10) is (√35, 243.43˚)