Help me!? I need to catch up On homework lol

Factor completely. 4p^2 + 36p + 81 express the answer in the form (ap + b)^2

What expression is equivalent to (84+16)

Will mark 50 show all what is the solution to the system of equations? use the substitution method and show your work. -5x+y= -3 -15 x+3y=7 explain what your answer in part (a) tells you about the association of the lines in this system.