Postulate 2.5 states that if two points lie in a plane, then the entire line containing those points lies in that plane.
Practice makes perfect
In the figure, CD and CE lie in plane P and DH and DJ lie in plane Q. Looking at the figure, we will state the postulate that can be used to show the given statement is true.
Statement
DA lies in plane P.
Let's identify plane P and draw DA.
As we can see the points A and D lie on plane P, so DA also lies in plane P. In this case, Postulate 2.5 can be used to show that the given statement is true.
If two points lie in a plane,
then the entire line containing those points
lies in that plane.
