Answer:
AD = 6 units
Explanation:
find the length of AD by taking the absolute value of the difference
A is positioned at - 6 on the number line and D at 0 , then
AD = | - 6 - 0 | = | - 6 | = 6 units
or
AD = | 0 - (- 6) | = | 0 + 6 | = | 6 | = 6 units