Which best proves why the expressions 4(x+3)+2x and 6(x+2) must be equivalent expressions?
when x= 3, both expressions have a value of 30.
when x=5, both expressions have a value of 42.
when x= 1, both expressions have a value of 18, and when x=8, both expressions have a value of 60.
when x= 2, both expressions have a value of 15, and when x-6, both expressions have a value of 39.