How do you convert the cartesian coordinate (2, -4) into polar coordinates?

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Answer 1 · 2017-09-11T17:31:27

see below

Use the formulas #x^2 + y^2 =r^2# and #tan theta =y/x#

#r^2=(2)^2+(-4)^2=4+16=20#

#r=sqrt20 = 2sqrt5~~4.472#

#tan theta = -4/2#

#theta=tan^-1 -2#

#theta ~~-1.107#

#:.(r,theta)~~ (4.472, -1.107)#