The expression 3(x-9) is equivalent to
3(x)+9.
3(x)+3(9).
3(x) – 9.
3(x) – 3(9).

option 4

Step-by-step explanation:

Distributive property: a(b + c) = a*b + a*c

3(x - 9) = 3*x - 3*9

Step-by-step explanation:

They are similar by angle-angle-angle.  While this is not a congruency theorem, it can be used for similarity.  Angle O is shared, so that is corresponding and also congruent, Angle OJK is corresponding to angle OMN and also congruent; and angle OKJ is corresponding to angle ONM and is also congruent.

They could also be similar by side-side-side since the corresponding sides are in the same proportion.  30/3 reduces down to 10/1.