Question

The radian measure equivalent to -45º is _____.

Answer 1

2pi radians=360 degrees
ratio and proprtion thing I guess

r/2pi=-45/360
r/2pi=-1/8
times both sides by 8pi
4r=-pi
divide both sides by 4
r=-pi/4

-pi/4 radians

Answer 2

(-π/4) ...... is the answer !!