Step by step
The question
Question: find out if the two lines are parallel.
The corresponding angles are 120° and 120°.
1 Name the angle pair
A line crosses two other lines.
It is called a transversal.
Our two angles are in the same place at each crossing: corresponding angles.
Together they make an F shape.
2 Use the parallel test
If the lines are parallel, both crossings look the same, so corresponding angles are equal.
And if they are equal, the lines are parallel.
120° and 120°: they are equal.
120 = 120
Careful!
For corresponding angles we ask: are they equal?
Careful: corresponding: equal, not adding to 180°
So the lines are parallel.
Answer: = parallel
We can draw the arrows on the lines now.
Let's look back.
First: name the angle pair.
Last: use the parallel test.
Answer
Answer: = parallel