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Ch. 1 - Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 21

You invested \$20,000 in two accounts paying 1.45% and 1.59% annual interest. If the total interest earned for the year was \$307.50, how much was invested at each rate?

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1
Define variables to represent the amounts invested: let \(x\) be the amount invested at 1.45%, and \(y\) be the amount invested at 1.59%.
Write an equation representing the total amount invested: \(x + y = 20000\).
Write an equation representing the total interest earned: \(0.0145x + 0.0159y = 307.50\).
Use the first equation to express one variable in terms of the other, for example, \(y = 20000 - x\).
Substitute this expression for \(y\) into the interest equation and solve for \(x\), then use the value of \(x\) to find \(y\).

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