Step by step
The question
Question: find out if the two lines are parallel.
The alternate angles are 50° and 50°.
1 Name the angle pair
A line crosses two other lines.
It is called a transversal.
Our two angles are between the lines, on opposite sides of the transversal: alternate angles.
Together they make a Z shape.
2 Use the parallel test
Parallel lines make alternate angles equal.
And if they are equal, the lines are parallel.
50° and 50°: they are equal.
50 = 50
Careful!
For alternate angles we ask: are they equal?
Careful: alternate: 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