Hi there.
The answer is (x-2y-8)(x-2y-4)
Explanation:

Let (x-2y) = x

Then factor the quadratic polynomial by 2 brackets factoring.

Then convert x to (x-2y)

The sum of the polygon is 27
Well,
For example
2.34 * 10^6 will be....
2,340,000
It is because if you have the positive powers, you move your decimal to the right. In this case the power is 6 so you move your decimal to the right 6 times.
Here's another example
1.23 X 10^-2
The answer will be 0.0123 because you move your decimal two the left two times. The power is negative 2 so you move it to the left.
Final tips: If you have positive power, move it to the right and if you have negative power, move it to the left.