Which equation is correct about the forces

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Homework Statement


Exam question diagram: a point with forces F pointing left, 20 N at angle θ above the horizontal to the right, and 15 N pointing straight down; the 20 N force is labelled with components 20 sin θ and 20 cos θ, with answer options A to D below.


The books answer is "D", no clue why though, Any one can explain?
Thank you
 
[strike]If you add those 15N and F, the resulting force has to have the same angle theta relative to the horizontal axis. If you draw a triangle there, you directly get the relation.[/strike]

Edit: Oh crap, Curious3141 is right. I did not check the result, just saw that you get the tan there.
And strictly speaking, there is a "N" missing as well.
 
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captinkareem1 said:

Homework Statement


Free-body diagram of a point with a 15 N force pointing down, a 20 N force at angle θ up and to the right, and a horizontal force F to the left, with handwritten 20 sin θ and 20 cos θ components, beside the multiple-choice question about equilibrium.


The books answer is "D", no clue why though, Any one can explain?
Thank you

All the given options are wrong. The correct answer is ##\displaystyle 15 = F\tan \theta##, which is not one of the given options, even though "D" is closest.