$\frac{-7 x}{ 5 y}$ 的数字系数是多少?
已知
给定的表达式是 $\frac{-7x}{5y}$。
要求
我们必须找到给定表达式的数字系数。
解答
数字系数定义为乘以变量的固定数字。
$\frac{-7x}{5y}=\frac{-7}{5}\times\frac{x}{y}$
因此,给定表达式的数字系数是 $\frac{-7}{5}$。
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