Skip to main content
Ch. 1 - Equations and Inequalities
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 2, Problem 75

Solve each equation. x3/2 = 125

Verified step by step guidance
1
Identify the equation given: \(x^{\frac{3}{2}} = 125\).
Recall that the exponent \(\frac{3}{2}\) means the square root of \(x\) raised to the third power, or equivalently, \((x^{\frac{1}{2}})^3\).
To isolate \(x\), raise both sides of the equation to the reciprocal power of \(\frac{3}{2}\), which is \(\frac{2}{3}\), so you get \(\left(x^{\frac{3}{2}}\right)^{\frac{2}{3}} = 125^{\frac{2}{3}}\).
Simplify the left side using the property of exponents: \(\left(x^{a}\right)^{b} = x^{a \cdot b}\), so \(x^{\frac{3}{2} \cdot \frac{2}{3}} = x^1 = x\).
Evaluate the right side by first finding the cube root of 125, then squaring the result: \(125^{\frac{1}{3}}\) and then square it to get \(125^{\frac{2}{3}}\).

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Rational Exponents

Rational exponents represent roots and powers combined. For example, x^(3/2) means the square root of x cubed, or (√x)^3. Understanding how to manipulate and interpret these exponents is essential for solving equations involving fractional powers.
Recommended video:
Guided course
04:06
Rational Exponents

Isolating the Variable

To solve equations like x^(3/2) = 125, you first isolate the variable expression. This often involves applying inverse operations such as raising both sides to the reciprocal power to undo the rational exponent and solve for x.
Recommended video:
Guided course
05:28
Equations with Two Variables

Properties of Exponents

Properties of exponents, such as (a^m)^n = a^(mn), help simplify expressions and solve equations. Applying these rules correctly allows you to manipulate the equation and find the value of the variable efficiently.
Recommended video:
Guided course
04:06
Rational Exponents