Expand the following. In other words, remove the parentheses (brackets): -5(2x - 4y)
B -10x + 20y
A 10xy
C -10x - 20y
D 10x - 20y

Could you make it more clear?

Use pythagorean’s theorem and find the missing side lengths of the two smaller triangles and add them together
13^2 - 12^2 = 5
15^2 - 12^2 = 9
5+9 = 14
14 is the length of each side of the square
14^2 + 14^2 = 19.8
19.8 is the diagonal length of the inside if the square