You can use the identity

The sign is negative because the angle is in the 3rd quadrant.
This corresponds to ...
a. -(4√17)/17
That dont een make no sense tho
(x + 11) *squared* +(y-12) *squared* = 49
Metallic ribbon: 16$ for 4ft
Dividing both sides by four, we get:
1 feet -- 4 dollars
White ribbon 3$ for 1 feet
1 feet -- 3 dollars
<h2><u><em>
Therefore, the Metallic ribbon costs more per feet.</em></u></h2>