9514 1404 393
Answer:
-8.21°
Step-by-step explanation:
The horizontal and vertical components of the forces are ...
(120; 30°) = (103.923, 60}
(200; -30°) = (173.205, -100}
Then the resultant is ...
(103.923 +173.205, 60-100) = (277.128, -40)
and the resultant direction is
arctan(-40/277.128) = -8.21°
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The polar coordinates (A; β) can be translated to rectangular coordinates by ...
(A; β) = (A·cos(β), A·sin(β))
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Additional comment
The semicolon in (A; β) signifies the ordered pair is polar coordinates (magnitude; angle). The comma in (x, y) signifies the ordered pair is rectangular (Cartesian) coordinates. This notation is borrowed from the GeoGebra app, a geometry graphing/calculating program. It avoids some confusion. Personally, I prefer the notation A∠β to signify a magnitude and direction in polar coordinates.
