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Ch. 5 - Systems of Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 6, Problema 43

In Exercises 43–46, let x represent one number and let y represent the other number. Use the given conditions to write a system of equations. Solve the system and find the numbers. The sum of two numbers is 7. If one number is subtracted from the other, their difference is -1. Find the numbers.

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1
Define the variables: let x represent one number and y represent the other number.
Translate the first condition 'The sum of two numbers is 7' into an equation: x + y = 7.
Translate the second condition 'If one number is subtracted from the other, their difference is -1' into an equation. This can be written as x - y = -1.
Set up the system of equations: \(\begin{cases}\) x + y = 7 \\ x - y = -1 \(\end{cases}\) .
Solve the system by adding the two equations to eliminate y: (x + y) + (x - y) = 7 + (-1). Simplify and solve for x, then substitute back to find y.

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