Question

Write -3r+3u in polar form PLEASE HELP

Answer 1

We have that
 -3r+3u

Step 1
Use the distance formula to find the radius
r = √(x^2 + y^2)
 (x,y)----------> (-3,3)
r= √(-3^2 + 3^2)=√18=3√2

Step 2
Use the tangent to find the angle  
θ = arctan(y/x)  
θ = arcTan(3/-3)= -45°-------> II Quadrant
then 
θ=180-45=135°

Step 3 
write in polar form
(x,y)------------> (r, θ)
so
(-3,3)----------> (3√2, 135°)

the answer is (3√2, 135°)