Consecutive Interior Angles: in Parallel Lines
How to solve the consecutive interior angles in parallel lines: formula, 1 example, and its solution.
Consecutive Interior Angles
By two lines and a transversal,
two pairs of consecutive interior angles are formed.
∠1 and ∠2
∠1' and ∠2'
Formula
Consecutive interior angles in parallel lines
are supplementary.
m∠1 + m∠2 = 180
m∠1' + m∠2' = 180
Example
Solution
Solution (Detail)
The given angles are
consecutive interior angles in parallel lines.
So the given angles are congruent.
So [5x + 60] + [70] = 180.
+60 + 70 = +130
Move +130 to the right side.
Then 5x = 50.
Divide both sides by 10.
Then x = 5.
So x = 5.