WEBVTT
00:00:01.000 --> 00:00:06.440
The figure shows a pair of parallel lines with a transversal drawn through them.
00:00:07.080 --> 00:00:09.240
This is a two-part question.
00:00:09.960 --> 00:00:17.240
The first part says, what name is given to the pairs of coloured angles highlighted in the figure?
00:00:18.640 --> 00:00:27.880
Interior angles, exterior angles, corresponding angles, or straight angles.
00:00:29.400 --> 00:00:43.160
So in the diagram, the parallel lines are the pair of horizontal lines and the transversal is the line highlighted in pink, which cuts through each of them.
00:00:44.440 --> 00:00:47.600
We’re asked to look at the pairs of coloured angles.
00:00:48.440 --> 00:00:53.560
Let’s look first of all at the positions of the pair of angles highlighted in green.
00:00:54.520 --> 00:00:59.000
Each of these angles are on the same side of the transversal.
00:00:59.680 --> 00:01:00.960
They’re on the right.
00:01:01.720 --> 00:01:07.360
They’re also the same side of the parallel lines.
00:01:08.200 --> 00:01:09.640
They are above them.
00:01:10.560 --> 00:01:15.920
These two criteria are what is necessary in order for a pair of angles to be corresponding angles.
00:01:16.640 --> 00:01:20.960
The same is true if we look at the pair of red angles.
00:01:21.800 --> 00:01:26.000
They’re on the same side of the transversal — the right.
00:01:26.680 --> 00:01:32.360
And they’re on the same side of the parallel lines — below.
00:01:33.400 --> 00:01:38.640
Therefore, these are also an example of corresponding angles.
00:01:39.920 --> 00:01:46.600
The exact same is true regarding the pair of blue angles and the pair of orange angles.
00:01:47.320 --> 00:01:56.160
And therefore, our answer to the first part of the question is that the name given to the pairs of coloured angles is corresponding angles.
00:01:57.320 --> 00:02:04.840
The second part of the question asks, what do you notice regarding the measures of two corresponding angles?
00:02:06.200 --> 00:02:11.520
This is why I didn’t write this part down straightaway because it rather gives the game away for the first part.
00:02:12.240 --> 00:02:21.760
The options are they are supplementary, they are complementary, or they are equal.
00:02:22.920 --> 00:02:29.400
Let’s just remind ourselves first of all what is meant by the term supplementary and complementary.
00:02:31.520 --> 00:02:49.240
A pair of angles are supplementary if their sum is 180 degrees, a pair of angles are complementary if they sum to 90 degrees, and of course, a pair of angles are equal if their measures are the same.
00:02:50.200 --> 00:02:58.360
So looking at the diagram, we can see that the measures of corresponding angles are the same in each case.
00:02:59.280 --> 00:03:15.440
Both orange angles are 135 degrees as are the two red angles and the blue angles are 45 degrees as are the two green angles.
00:03:16.520 --> 00:03:25.600
Therefore, our answer to the second part of the question regarding the measures of corresponding angles is that they are equal.