Video Transcript
In the given figure, which of the
following would represent the straight line passing through 𝐵 and 𝐶?
The given figure that our question
mentions is this diagram here. We can see that it’s made up of
four points labeled 𝐴, 𝐵, 𝐶, and 𝐷. And these are connected together by
two paths. We’ve got a line segment that
connects 𝐴 and 𝐵, and we’ve got another path that seems to start at 𝐵, pass
through 𝐶 and also 𝐷.
Our question asks us how we would
represent the straight line that passes through points 𝐵 and 𝐶. But before we look at our possible
answers, let’s think about what this question means because at the moment we can’t
see a straight line that passes through points 𝐵 and 𝐶. In maths, a line is something very
definite. It’s a straight path that continues
in both directions and doesn’t end. If we look at our diagram, we can
see that we do have an endpoint.
At the moment, the path that goes
through points 𝐵 and 𝐶 starts at point 𝐵. It does pass through 𝐶. And we can see by the arrowhead
that it does continue on and on, but only in one direction. If we’re looking for the straight
line that passes through 𝐵 and 𝐶, we’re looking for something that continues in
both directions.
Now, it’s still there, even though
it’s not drawn on the diagram. Let’s use our pink pen to show how
this line is going to continue. It’s going to carry on past 𝐵 on
and on. That’s better. Now, we can imagine what a straight
line that passes through both 𝐵 and 𝐶 would look like. But how would we represent
this?
Underneath the diagram, we can see
five possible answers. We can work out which one’s correct
because we know that a straight line continues in both directions. Two of our possible answers have a
short line above them with an arrowhead at one end. These are mini versions of rays,
not straight lines. We know this because a ray starts
from an endpoint and then just continues in one direction. That’s why there’s one
arrowhead. The last answer doesn’t have any
arrowheads. This represents a line segment, in
other words, part of a line between two endpoints. The correct answer of course is
this one here.
The symbol at the top is a mini
version of a line. Of course, it’s continuing in both
directions. That’s why there are two
arrowheads. And the letters 𝐵 and 𝐶 tell us
two points that our straight line passes through. This is the correct symbol that
represents a straight line that passes through points 𝐵 and 𝐶. And we’d read it as line 𝐵𝐶.
