There is a figure q1= 23 uC and q2= 16 uC. The force on q1 points in the -x direction.

q1 is at (0,1)
q2 is at (2,0)
q3 is at (2,2)

What is the magnitude of the force on q1?

I am doing this

(9*10^9)(23*16)(-4ihat)7^3

where did i go wrong?