Answer :

konrad509
x - number of apples Anna had

[tex]\dfrac{x}{2}+3=17|\cdot 2\\ x+6=34\\ x=28[/tex]
x - number of apples Anna had, so you need to do this:
x/2+3=17| * 2
x+6=34        
x+28
show the process
It makes it equal 28, the number Anna had originally