X + y = 6
x - 6y = -9
Subtract the equations, you get:
y - (-6y) = 6 - (-9)
7y = 15
y = 15/7
x + 15/7 = 6
x + 15/7 = 42/7
x = (42-15)/7
x = 27/15
None of your answer choices are correct, since the solution to the systems of equation is (27/15, 15/7)
Perimeter is
2 • width+ 2•length=
2• (4x-4)+2•(2x+5)=
Distribute multiplication in parentheses
8x-8+4x+10=
Combine like terms
12x+2
The greatest common factor of those numbers is 8.
