Question

Please help me out. :)

Answer 1

You can find the magnitude of F by summing forces:
\[\Sigma F = Resultant\]
The location of F can be found by summing moments:
If you take moments about C (where the resultant passes)
\[\Sigma F*d =0\]
This means
\[100*45+F*(45-x)-300*25=0\]
You can then solve for x.

Answer 2

still looking for help ?

Answer 3

i dont know

Answer 4

yes? :)

Answer 5

Since all the three forces are in same direction, simply adding their magnitudes gives you the resultant force :

\[\large 100+F+300 = 600\]

solve \(F\)

Answer 6

now its easy

Answer 7

F = 200. :)

Answer 8

yes! plug that in the second equation given by @mathmate and solve x :

\[\large 100*45+F*(45-x)-300*25=0\]

Answer 9

x = 30. :)