Simple Voltage and Electric Field Question

A given system has the equipotential surfaces shown in the figure below, where V0 = 14.0 V.

http://www.webassign.net/walker/20-26alt.gif

What is the x-component of the electric field?

edit:

to get the correct answer for the x-component of the electric field, I divided 14 V by 0.04 m.

However, if you look at the image, 4 cm in the x-direction looks to be only half of the V0 line (V0 continues downwards up until 8 cm in the x-direction). If we only use half voltage line's distance, shouldn't we only use half V0's voltage (so half of 14 is 7)? But instead, we use all of the 14V, which confuses me.