For this case, the first thing we must do is find the multiples of the coefficients.
We have then:
- 42: 1, 2, 3, 6, 7, 14, 21, 42
- 56: 1, 2, 7, 8, 28, 56
We observe that the biggest common factor is given by 7.
Therefore, by rewriting the expression we have:

Answer:
An equivalent expression is given by:
