Chapter 7 Exponential and Logarithmic Functions - 7.6 Solve Exponential and Logarithmic Equations - 7.6 Exercises - Mixed Review - Page 522: 63

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Given: $5x-y=7\\2x+5y=-3$ Multiply both sides of the first equation by $5$, and then add it to the second equation: $27x=32$ Solve for x: $x=\frac{32}{27}$ Find y: $2(\frac{32}{27})+5y=-3\\5y=-\frac{145}{27}\\y=-\frac{29}{27}$