### Home > MC2 > Chapter 2 > Lesson 2.1.2 > Problem 2-30

2-30.

In parts (a) and (b) below, copy the number lines and use them to show the solution to the problems.

The answer is where the point moves to.

Show

on a number line. See parts (a) and (b) for help.

Rachel said that

will be positive because two negatives always give a positive. Draw the problem on a number line, then explain whether you agree or disagree with Rachel.

Explain why a negative number plus a negative number is always a negative number.