The Number System

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- Know that there are numbers that are not rational, and approximate them by rational numbers.

# Know that there are numbers that are not rational, and approximate them by rational numbers.

### Lessons for this standard

Resources cannot be aligned to this standard, browse sub-standards to find lessons.

### Related standards

- This standard is part of: MGSE8.NS
- This standard is derived from: CCSS.Math.Content.8.NS.A

#### More specific sub-standards

Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.

Use rational approximation of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line, and estimate the value of expressions (e.g., estimate π² to the nearest tenth).

#### Similar standards in other grades

Find and position integers and other rational numbers on a horizontal or vertical number line diagram; find and position pairs of integers and other rational numbers on a coordinate plane.

Understand a rational number as a point on the number line. Extend number line diagrams and coordinate axes familiar from previous grades to represent points on the line and in the plane with negative number coordinates.

Find and position integers and other rational numbers on a horizontal or vertical number line diagram; find and position pairs of integers and other rational numbers on a coordinate plane.

Understand a rational number as a point on the number line. Extend number line diagrams and coordinate axes familiar from previous grades to represent points on the line and in the plane with negative number coordinates.

#### Similar standards elsewhere

Know that there are numbers that are not rational, and approximate them by rational numbers.

Know that there are numbers that are not rational, and approximate them by rational numbers.

Know that there are numbers that are not rational, and approximate them by rational numbers.

Know that there are numbers that are not rational, and approximate them by rational numbers.

Know that there are numbers that are not rational, and approximate them by rational numbers.