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\begin{aligned} &1=\frac{y^{2}}{49}-\frac{x^{2}}{32} \\ &1=\frac{y^{2}}{49}-\frac{0^{2}}{32} \\ &1=\frac{y^{2}}{49} \\ &y^{2}=49 \\ &y=\pm \sqrt{49}=\pm 7 \end{aligned}