I think you are missing something, what expression?
If you mean the • dot, it means multiplication.
The answer is C. Because the side triangles inner corner is 51 so the inner corner of the big train fled are 129. 129 + 20 equals 149 and 180 - 149 equals 31.
For anyone else who needs the right answer...it’s “parallel to the base”. I just did it and I got it right.
Answer:
1/x^3
Step-by-step explanation:
foil method