PSAT 8/9 P2 · 第 15 题

PSAT 8/9 P2 · 原库模块 3 · Q15 原库参考解析

Line h is defined by \( \frac{1}{5}x+\frac{1}{7}y-70=0 \) . Line j is perpendicular to line h in the xy-plane. What is the slope of line j?

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