## anonymous 5 years ago The polar coordinates of a certain point are r=5.05 cm, @(theta)= 250 degrees. (a) Find its Cartesian coordinates x and y. (d) Find the polar coordinates of the points with Cartesian coordinates (3x, −3y). Show work.

1. anonymous

a. Polar->Cartesian $x= rcos(\theta);y= rsin(\theta)$ r=5.05 , theta= 250 degrees $x= rcos(\theta)$$=5.05cos(250)$$=-1.727$ $y= rsin(\theta)$$= 5.05sin(250)$$=-4.745$ b.Cartesian->Polar (3x, −3y) $r=\sqrt(x^2+y^2);\theta=\arctan(y/x)$ $r=\sqrt(x^2+y^2)$$=\sqrt((3x)^2+(-3y)^2)$$=\sqrt(9x^2+9y^2)$$=\sqrt(9(x^2+y^2))$$=3\sqrt(x^2+y^2)$ $\theta=\arctan(-3y/3x)$$\theta=\arctan(-y/x)$ Where the x and y points supposed to be (3,-3) or (3x,-3y)?

2. anonymous

*Were

3. anonymous

The last.

4. anonymous

Okay well then the answer above are for the last. That's as far as you can go :)