Squaring both sides of the given equation: w^2=7w, or w^2-7w=0.
w^2-7w=0 can be factored: w(w-7)=0. Then, w=7 or w=0. Both 0 and 7 are solutions of this equation.
This is the concept of geometry, the total sum of angles in a hexagon is given by:
(n-2)*180
=(6-2)*180
=720
the size of each interior angle will be:
120°
N/B
the exterior and interior angles are supplementary to each other.
Therefore the size of the exterior angle will be:
180-120
=60°
the answer is A