Answer: F$_1$ = 22N (Up) and F$_2$ = 13 N (Left).
According to Newton’s first law, since the object is at rest, the net force must be zero. Choose up as positive. So down is negative.
Consider the forces along the x-axis:
If Net force $= 0 \rightarrow 0 = 28N - 15N - F_2 \rightarrow F_2 = 13N $ (Left)
Consider the forces along the y-axis:
If Net force $= 0 \rightarrow 0 = 22N - F_1\rightarrow F_1 = 22N $ (Up)