Susan have 9 books.
Explanation:
Given that Marge has 4 more than 2 times as many books as Susan.
Let x represents the number of books that Susan has.
The relationship is written as
[tex]4+2x=22[/tex]
To find: Number of books that Susan have.
The number of books that Susan have can be determined by solving the expression for x.
Thus, we have,
[tex]4+2x=22[/tex]
Subtracting 4 from both sides of the equation, we get,
[tex]2x=18[/tex]
Dividing both sides by 2, we get,
[tex]x=9[/tex]
Therefore, Susan has 9 books.