Common Core Math - Grade 8

Lesson Plan

Use square root and cube root symbols to represent solutions to equations

Goals / Objectives

Use the square root symbol to represent solutions to equations of the form x^2 = p, distinguishing between the principal root sqrtp and the two solutions x = +/-sqrtp

Use the cube root symbol to represent solutions to equations of the form x^3 = p, recognizing that each such equation has exactly one real solution x = cbrtp

Evaluate square roots of perfect squares (1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144) and cube roots of perfect cubes (1, 8, 27, 64, 125) from memory

Evaluate square roots and cube roots of positive rational numbers that are perfect squares or perfect cubes, including fractions such as sqrt(1/4) = 1/2 and cbrt(1/8) = 1/2

Identify sqrt2 as irrational and explain that square roots of non-perfect-squares (such as sqrt3, sqrt5, sqrt7) are irrational numbers whose decimal expansions neither terminate nor repeat

Standards

8.EE.A.2

8.EE.A.2: Use square root and cube root symbols to represent solutions to equations of the form x^2 = p and x^3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that sqrt2 is irrational.

Academic Vocabulary

Not in our source material

Accommodations

Not in our source material

Anticipatory Set / Bell Work

Sign in to see this

Check for Understanding

Sign in to see this

Guided Practice

Independent Practice

Lesson plan — Use square root and cube root symbols to represent solutions to equations | K12worX