Answer:
[tex]\angle ECD = 115[/tex]
Step-by-step explanation:
Given
[tex]\angle ACB = 65[/tex]
Required
Determine [tex]\angle ECD[/tex]
From the attached image, we have:
[tex]\angle ACB +\angle ECD = 180[/tex] ---- angle on a straight line
This gives:
[tex]65 +\angle ECD = 180[/tex]
Subtract 65 from both sides
[tex]\angle ECD = 180 - 65[/tex]
[tex]\angle ECD = 115[/tex]