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Exercises Systems of equations

Example 5.13 from Elementary Algebra, 5.2 Solve Systems of Equations by Substitution

Solve Systems of Equations by Substitution: example 5.13

Solve the system by substitution. ${\begin{matrix} 2 x + y = 7 \\ x - 2 y = 6 \end{matrix}$

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Solve the system by substitution. ${\begin{matrix} −2 x + y = −11 \\ x + 3 y = 9 \end{matrix}$

How did it go?

PreviousSolve Systems of Equations by Graphing: example 5.12 Next Solve Systems of Equations by Substitution: example 5.14

From Elementary Algebra (1st edition) by OpenStax (Rice University), section 5.2, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.