There is a 85uC point charge at the origin. Find the electric field at the point x3= -45cm , y3= 55cm

Question

There is a 85uC  point charge at the origin. Find the electric field at the point  x3= -45cm ,  y3= 55cm

(5.85*10^5)(-.45+.75)/(-.45^2+.75^2)^3/2  am I totally off

The previous questions before this were to find at x1=40cm y1=0 and
x2=65cm y2=65cm

I figured those out, but can't get this one.

bobpursley · Answer

If you want the magnitude of E, you are way off.

E=Kq/r^2=k(.85E-6)/(.45^2+.75^2)

Now if you want E as E=Ex + Ey as a vector, you have to do it as a vector equation. I have no idea how you got the numbers and powers in the equation you typed.