Sure! Let Kara's age be [tex]\( n \)[/tex]. According to the problem:
1. Cassie's age is 3 less than twice Kara's age. So Cassie's age can be written as [tex]\( 2n - 3 \)[/tex].
2. The sum of their ages is 42.
So, we can set up the equation as follows:
[tex]\[ n + (2n - 3) = 42 \][/tex]
Now, let's break it down into the boxes:
[tex]\[ n + ( \boxed{2} n - \boxed{3} ) = \boxed{42} \][/tex]