x=20
AD= 23
DC= 23
AC= 46
The median means both sides of the line AC are equal.
Therefore: x+ 3 = 2x-17
and we can solve this for x
Subtract x from both sides
x-x = 2x-x -17
3 = x -17
Add 17 to both sides
3 +17 = x -17+17
20 = x
The length of AD is x + 3, replace x with 20:
20 + 3 = 23
The length of DC is the same as AD (because they’re separated by the median) so DC= 46
AC is the length of AD + DC,
23+23= 46.
AC= 46