### Home > CCA2 > Chapter 2 > Lesson 2.1.4 > Problem2-53

2-53.

Throughout this book, key problems have been selected as “checkpoints.” Each checkpoint problem is marked with an icon like the one at left. These checkpoint problems are provided so that you can check to be sure you are building skills at the expected level. When you have trouble with checkpoint problems, refer to the review materials and practice problems that are available in the Checkpoint Materials.

This problem is a checkpoint for finding the distance between two points and finding the equation of a line. It will be referred to as Checkpoint 2A.

For each pair of points, determine the distance between them. Then find the equation for a line through them. Homework Help ✎

1. $(−2,4)$ and $(4,7)$

1. $(3,4)$ and $(3,−1)$

1. $(−7,20)$ and $(3,−5)$

1. $(1,−2)$ and $(5,−2)$