Answer
34
Work Step by Step
The single hash marks tell us that $\overline{AC}$ is congruent to $\overline{DC}$.
$AC=DC$
Substitute:
$4x+5=3x+8$
Subtract 3x from each side:
$4x+5-3x=3x+8-3x$
$x+5=8$
Subtract 5 from each side:
$x+5-5=8-5$
$x=3$
Segment Addition Postulate:
$AC+DC=AD$
Substitute
$(4x+5)+(3x+8)=AD$
Combine like terms:
$7x+13=AD$
Substitute:
$7(3)+13=AD$
$21+13=AD$
$34=AD$
