S. D. V. Stephens

notes / Integrated Mathematics / chapter 9: Intermediate Algebra (Art of Problem Solving)

1 Basic Techniques for Solving Equations

Problem 1.11.

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Substitute the third equation into the second: Then , and the first equation becomes With the system is From : , so . Then , so , , and .

Example 1.1.

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Idea: choose , so that only has one variable.

Or substitute: from the first equation , so So the power of in is , i.e. and . Then and indeed . So , .

Problem 1.31. Win ratio . At the start of the weekend . Over the weekend: matches, won and lost. At the end, . What is the largest number of matches won before the weekend began?

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, and

1.1 Isolation

Problem 1.1. (a)

(b)

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(a) .

(b) .

Problem 1.2. (a)

(b)

(c)

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(a) .

(b) .

(c) .

Problem 1.3. Compute and solve: .

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.

Problem 1.4. Compute and solve:

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Moving the first fraction across, , so

Problem 1.5. Find all such that has no solution for .

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No solution is when , i.e. .

Also causes division by in the original equation. So set no solution, so there are no values of for which . Note is also not a solution.

So and are the two values which give no solution.

Exercises

Exercise 1.1.4. Find all such that has no solution for .

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