Answer: Linear Pair Theorem
Step-by-step explanation:
Linear Pair Theorem says that if two angles forjm linear pair then they are supplementary.
Given : ∠ABC and ∠CBD are a linear pair.
Since linear pair is supplementary.
And supplementary angles area dded up to 180 degrees.
Then, ∠ABC +∠CBD = 180° (1)
Also, if m∠ABC = m∠CBD = (2x − 8)° [given] (2)
Then, from (1) and (2), we have
Divide both the sides by 4 , we get
Hence, the correct answer is Option (B) "Linear Pair Theorem"