For activities with important visual aids. Unit: 8.8 Pythagorean Theorem and Irrational Numbers (Grade 8). 8.8 Pythagorean Theorem and Irrational Numbers In this unit, students work with geometric and symbolic representations of square and cube roots. They understand and use notation such as \(\sqrt 2\) and \(\sqrt[3]{5}\) for square and cube roots. They understand the terms “rational number” and “irrational number,” using long division to express fractions as decimals. They use their understanding of fractions to plot rational numbers on the number line and their understanding of approximation of irrationals by rationals to approximate the number-line location of a given irrational. Students learn