-11 = -5 + 6n + 6 WHAT DOES "N" EQUAL?

Arectangle has an area of 54 square feet. if the length is 3 feet more than the width, find the dimensions of the rectangle.

In the figure below, ∠dec ≅ ∠dce, ∠b ≅ ∠f, and segment df is congruent to segment bd. point c is the point of intersection between segment ag and segment bd, while point e is the point of intersection between segment ag and segment df. the figure shows a polygon comprised of three triangles, abc, dec, and gfe. prove δabc ≅ δgfe.

How to simply and write the answer n a whole number