- Here, CD and DE are equal.
- Therefore, by the problem
- CD = DE
- or, 7a + 11 = 10a + 2
- or, 10a - 7a = 11 - 2
- or, 3a = 9
- or, a = 3
- Therefore, CD = 7a + 11 = 7(3) + 11 = 21 + 11 = 32
Answer:
32
Hope you could get an idea from here.
Doubt clarification - use comment section.