In this question it is given that the values of CD and CE are 20 and 32 respectively.
Since the length of CE is greater then of CD, so C and D could not be the end points.
Therefore, either D and E are the endpoints or C and E are the endpoints.
If D and E are the endpoints, then DE is the sum of 20 and 32 which is 52.
And if C and E are the endpoints, then DE is the difference of CE and CD that is 12.
So the possible values of DE are 12 and 52.
