# How do you convert (15, -3) into polar coordinates?

##### 1 Answer

Jan 20, 2016

# (sqrt234 , - 11.3^@ ) #

#### Explanation:

To convert from Cartesian coordinates to Polar . Use the

following formulae.

#• r^2 = x^2 + y^2 #

#• tantheta = (y/x) # In this question x = 15 and y = - 3

so

# r^2 = 15^2 + (- 3 )^2 = 225 + 9 = 234 rArr r = sqrt234# and

# tantheta = (-3/15) rArr theta = tan^-1 (-3/15) = - 11.3^@# Note : ( 15 , - 3 ) is a point in the 4th quadrant and so

#theta # must

be in this quadrantSince negative angles are measured from the x-axis in a

clockwise direction then#theta = -11.3^@# is in this quadrant.