What is the force on the -10nC charge?

Question

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Answer 1

F1= k[ (5 x 10)xE-9/(.01)^2 ] F1 is in negative y direction (-j)
F2 = k[ (15 x 10)xE-9/((.03)^2 + .01 ^2)]

F2x= F2cos (A)
F2x= F2sin(A)

A=arcTan(1/3)

Ft=( F2x ) i - ( F1 + F2y )j