Question

The model shows the expression 21 + 9.

A model with 3 rows of 7 squares and 3 rows of 3 squares.

Which expression is equivalent to this sum?
3 (7 + 3)
3 (7) + 3
3 + 7 + 3
7 (3 + 3) i need it now

Answer 1

the first expression is equivalent to this sum

Explanation:

3(7+3)

3×7+3×3

21+9

30