<span>4x(5y-x)-5y(4x-y)=20xy-4x^2-20yx+5y^2=-4x^2+5y^2=5y^2-4x^2</span>
Answer:

Step-by-step explanation:
The first step is to multiply the numbers of the numerator. Thus:


Writing the answer above as the product of a whole number and unit fraction (that is, mixed number), 5 goes in 8 1 time remainder 3. Therefore:

The greatest common factor is the term in which the variable is raised to the lower power. this can be factored out of all terms, and is the greatest factor that can do so.
the 2 parallel lines mean that the lines are equal
SO since BD = 18, DC is also 18