Help with Combining Oblique Vectors

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SUMMARY

The discussion focuses on the vector addition problem involving three forces: R = 3.5N[350], Q = 2.75N[125], and S = 2.15N[0]. The user initially calculated the resultant vector incorrectly, arriving at R + Q - S = 1.54[39°]. However, the correct calculation revealed that S contributes a value of 2.15 along the x-axis, leading to the correct resultant of 1.67[99.68°]. The error stemmed from neglecting the x-component of the vector S.

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Homework Statement


R = 3.5N[350] Q = 2.75N[125] S = 2.15N[0]

R + Q - S

The Attempt at a Solution



Finding x and y for 3.5N[350]
Sin80 = y/3.5 = -3.45
Cos80 = x/3.5 = 0.61

y = -3.45
x = 0.61

Finding x and y for 2.75N[125]
Sin35 = x/2.75 = -1.58
Cos35 = y/2.75 = 2.25

x = -1.58
y = 2.25

Finding x and y for 2.15[0]
x = 0
y = 0
(Since it's at 0)

Rx = 0.61 - 1.58
Rx = -0.97

Ry = -3.45 + 2.25
Ry = -1.2

a^2+b^2 = c^2
c=1.54

Tanθ=0.97/1.2
θ=39°

When I check the answer, it shows 1.67[99.68°] instead of my answer 1.54[39°].

What did I do wrong?
 
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Solved it...forgot that 2.15[0] had a x..which is 2.15.
 

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