Sal was finding the perimeter of the given rectangle. He wrote this expression: (3x+3x)+(4x+4x)+(3+3). Which expressions are equivalent? Choose all that apply.
a.2(3x) +2(4x+3)
b.3x+3x+4x+3+4x+3
c.4(3x) +2(4x)
d.3+3+x (3+3+4+4)e.20x