How do I convert polar coordinates (10,π4) to rectangular coordinates?

1 Answer
Aug 14, 2014

The answer is (50,50).

This problem is solved using trigonometry. I like to use the mnemonic SYR, CXR, TYX (pronounced sir kicks'er ticks). sinθ=yr,cosθ=xr,tanθ=yx.

So rearranging with algebra, we get x=rcosθ,y=rsinθ.

Next, substitute the polar coordinates. Make sure that your calculator is in RAD mode. However, π4 is a special angle that you should memorize the ratios.

x=10cos(π4),y=10sin(π4)

π4 is in the fourth quadrant, this corresponds with (50,50).