Answer:
<ADC = 131
Step-by-step explanation:
< ADC = <ADB + < BDC
The large angle is the sum of the two smaller angles.
<ADC = 89+42
=131
131 degrees
The reason for, is since <ADC is equal to < ADB + <BDC and that we already know the values of <ADB and <BDC, we can simply do
89 + 42 = 131.
So, <ADC is 131 degrees.
:)
