By definition, an equation has no solution when does not exist a value of the variable that makes the equation true.
• In this case, you have this expression on the left side of the first equation:
Then, knowing part of the right side, you can set up the following:
Notice that you need to write a value different from 6, in order to make the equation false, In this case, you cannot complete the missing value with 2, because;
Then, having that equation. you can solve it as follows:
• Given the second equation that has this left side:
The missing value must be: