Exercise 27 Page 393

Practice makes perfect

If three points are collinear, you can say that the middle point is between the other two points.

Since the points A, B, and C are on a straight line, and B is in the middle, the statement is true.

Three points are collinear if all of them are on a straight line.

Point C is not on a straight line with B and E. Therefore, the statement is false.

As we can see in the picture, the points A, D, and H are on a straight line.

Hence, they are collinear and we can say that point D lies between points A and E. The statement is true.

If we look very closely, we can see that there is not a straight line between C, E, and F. The direction changes slightly between CE and EF.

Since the points are not collinear, we cannot say that E is between C and F. Therefore, the statement is false.

Communicate Your Answer p.387

Monitoring Progress p.388-391

Exercises p.392-394

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