Find the rectangular coordinates for the point whose polar c

Find the rectangular coordinates for the point whose polar coordinates are given. (9 Squareroot 2, -pi/4) (x, y) = (________)

Solution

The rectangular coordinates (x,y) and polar coordinates (R,theta) are related as

x= R sin theta, y= R cos theta

we have (9sqrt 2,-pi/4)

x=9sqrt2 sin (-pi/4) y= 9sqrt2 cos(-pi/4)

x=-9, y=9

Therefore rectangular coordinate is (-9,9)