Answer:
4(3x+y)^2
Step-by-step explanation:
36x^2+24xy+4y^2
=9*4x^2+6*4xy+4y^2
=4(9x^2+6xy+y^2)
=4(3x+y)*(3x+y)
=4(3x+y)^2
40 cm
Perimeter of a square = 4a
=4 ( 10 )
=40cm
Have a nice day!