The equation for this would be 6x=42
Here's an explanation.
You have 6 sheets of paper, and you draw some number of stars on each paper. The number of stars are the same. Let's put the stars one each paper as x. Now it's also given that the total number of stars are 42. Since there are x stars on each paper, then 6 times x would be the total number of stars, which is 42. So 6x=42, and x=7