A plane can be named using any three non-collinear points contained in the plane.
Example Solution: RST
Practice makes perfect
In this exercise we want to find another name for plane V. A plane can be named using any three non-collinear points contained in the plane. Therefore, we are interested in all the points contained in plane V. First, let's take a look on the given diagram and mark these points.
There are four points that lie in plane V: Q, R, S, and T. However, Q, R, and S are collinear, so we cannot use these to name the plane. Instead, we can use T and any two of the other three points. One example of a correct name for this plane is RST.
Extra
Alternative Answers
We have stated before that to name a plane we need three non-collinear points. Since Q, R, and S are collinear, we can only use two of these points and another point non-collinear with them T. This means that plane V can be named in various ways using any combination of these points. Let's write all possible combinations, considering the names of the points in alphabetical order.
RST, QRT, QST
As the example answer to the exercise we chose RST, but each of these options is correct.
