Chapter 4 Quadratic Functions and Factoring - 4.10 Write Quadratic Functions and Models - 4.10 Exercises - Mixed Review - Page 315: 64

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Given: $2x+3y=-1\\10x+7y=-1$ Multiply the first equation by $-5$: $-10x-15y=5$ Then add it to the second equation: $-8y=4\\ \rightarrow y=-\frac{1}{2}$ Substitute: $2x+3(-\frac{1}{2})=-1\\ \rightarrow 2x=\frac{1}{2}\\ \rightarrow x=\frac{1}{4}$