Skip to main content
Ch. 1 - Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Not the one you use?Change textbook
Chapter 2, Problem 3

In Exercises 1–26, solve and check each linear equation. 7x - 5 = 72

Verified step by step guidance
1
Start with the given linear equation: \$7x - 5 = 72$.
Add 5 to both sides of the equation to isolate the term with \(x\): \$7x - 5 + 5 = 72 + 5\( which simplifies to \)7x = 77$.
Divide both sides of the equation by 7 to solve for \(x\): \(\frac{7x}{7} = \frac{77}{7}\) which simplifies to \(x = 11\).
Check your solution by substituting \(x = 11\) back into the original equation: \$7(11) - 5$.
Simplify the left side to verify it equals 72: \$77 - 5 = 72\(, confirming that \)x = 11$ is the correct solution.

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.

Linear Equations

A linear equation is an algebraic equation in which each term is either a constant or the product of a constant and a single variable. It forms a straight line when graphed and typically has the form ax + b = c. Solving linear equations involves finding the value of the variable that makes the equation true.
Recommended video:
06:00
Categorizing Linear Equations

Isolating the Variable

To solve a linear equation, you must isolate the variable on one side of the equation. This involves performing inverse operations such as addition, subtraction, multiplication, or division to both sides, maintaining equality. For example, to solve 7x - 5 = 72, add 5 to both sides before dividing by 7.
Recommended video:
Guided course
05:28
Equations with Two Variables

Checking the Solution

After finding the value of the variable, substitute it back into the original equation to verify the solution. This ensures that the left and right sides of the equation are equal, confirming the correctness of the solution. Checking helps avoid errors made during the solving process.
Recommended video:
05:21
Restrictions on Rational Equations