Two supplementary angles have the following measures: m∠ABC=135° and m∠CBD=9x° . What is the equation to solve for x ?

1 answer

Since ∠ABC and ∠CBD are supplementary angles, their measures sum up to 180°. Therefore, we can write the equation:

m∠ABC + m∠CBD = 180°

Substituting the given values:

135° + 9x° = 180°