If the rectangle has a fixed width of 300, it means that

where
and
are width and length, respetively.
So given the length
, the are would be

(9)(3) would be the expression for the factors rounded to the nearest whole numbers.
I hope I correctly answered your question and that this helps.
Step-by-step explanation:
Please specify values so we may answer. Judging by the looks of the question, this uses the concept of similarity
∠ABC is 180°. ∠ABC-∠ABD=68°. Since line BE ∠DBC, 68 divide by 2 is 34°. So ∠EBC is <span>34°.</span>