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Ch. 1 - Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Not the one you use?Change textbook
Chapter 2, Problem 103a

In Exercises 99–106, solve each equation. 0.7x + 0.4(20) = 0.5(x + 20)

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1
Distribute the constants to simplify the equation. For the term 0.4(20), multiply 0.4 by 20. Similarly, distribute 0.5 to both terms inside the parentheses in 0.5(x + 20).
Rewrite the equation after distribution. It will look like: 0.7x + 8 = 0.5x + 10.
Isolate the variable term on one side of the equation. Subtract 0.5x from both sides to get: 0.7x - 0.5x + 8 = 10.
Simplify the coefficients of x on the left-hand side. Combine like terms to get: 0.2x + 8 = 10.
Isolate x by subtracting 8 from both sides, then divide by 0.2 to solve for x. The equation will become: x = (10 - 8) / 0.2.

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Key Concepts

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

Linear Equations

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