Which point has the strongest electric field strength in this scenario?

[Cici2017]

Homework Statement

Homework Equations

The Attempt at a Solution

I tried to use the formula: F=kq₁q₂/r²
So at point B, the electric field strength is( 2kQ/r²) - (-kQ/r²)= 3kQ/r²
At A: (2kQ/r²)+(-kQ/r²)=kQ/r²
At C: -(2kQ/r²)-(-kQ/r²)=-kQ/r²
So B is the strongest?
Is there an easier way to do it?

 

[haruspex]

Is there an easier way to do

B is the only one where the two fields reinforce, so it is a good candidate. It could only lose to A or C if those were significantly closer to one of the charges.