Page 161 - ABCTE Study Guide_Neat

Answer

The correct answer is B. The category of rational numbers is a subset of real numbers, as shown on the
diagram. You can ccorrect statements A and D by changing the first words to “some.” Correct C by
making the first word “all.”

You may be thinking the whole thing is irrational at this point. Let's take these numbers and lay them out
in a traditional way.

What Can You Do With a Number Line?

You can do more than you might have thought you could, especially if you haven’t thought about it in a
few years. Today, students of all ages use number lines for a wide variety of mathematical tasks,
including:

• counting
• math operations
• measuring
• graphing
• estimating

Many students want all of their number lines to start at zero, but a number line can start and end at any
number.

Number lines are frequently used to show the solutions to inequalities.
For example: Solve . The solution is ; any number greater than 5 makes the inequality true.
Shown on the number line, it looks like this:

An empty dot shows that the number is not included in the solution.

If the problem had been , then the solution would have been . On the number line, the dot on
the 5 would be solid, showing that 5 is included in the solution.