5.51 Упростите выражение и подчеркните его коэффициент: 5 1 a)-x(-); B)-x(-2); ) . (-70). 2; 96.3z. 20 9 9 4 5 7 5 4 a . б) a a г) -x y 20 8 12 15

• а) - \(\frac{5}{6}\) x \(\cdot\) ( - \(\frac{1}{5}\) y ) = \(\frac{5}{6}\) \(\cdot\) \(\frac{1}{5}\) xy = \(\frac{1}{6}\) xy. Коэффициент: \(\frac{1}{6}\)
• б) - \(\frac{4}{7}\) a \(\cdot\) ( - \(\frac{7}{8}\) a ) = \(\frac{4}{7}\) \(\cdot\) \(\frac{7}{8}\) a\(^2\) = \(\frac{1}{2}\) a\(^2\). Коэффициент: \(\frac{1}{2}\)
• в) - \(\frac{20}{9}\) x \(\cdot\) ( - \(\frac{9}{4}\) z ) = \(\frac{20}{9}\) \(\cdot\) \(\frac{9}{4}\) xz = 5xz. Коэффициент: 5
• г) \(\frac{5}{12}\) x \(\cdot\) ( - \(\frac{4}{15}\) y ) = - \(\frac{5}{12}\) \(\cdot\) \(\frac{4}{15}\) xy = - \(\frac{1}{9}\) xy. Коэффициент: - \(\frac{1}{9}\)
• д) \(\frac{3}{8}\) n \(\cdot\) ( - \(\frac{7}{6}\) b ) \(\cdot\) \(\frac{2}{7}\) z = - \(\frac{3}{8}\) \(\cdot\) \(\frac{7}{6}\) \(\cdot\) \(\frac{2}{7}\) nbz = - \(\frac{1}{8}\) nbz. Коэффициент: - \(\frac{1}{8}\)
• e) \(\frac{5}{9}\) a \(\cdot\) \(\frac{9}{20}\) b \(\cdot\) 3z = \(\frac{5}{9}\) \(\cdot\) \(\frac{9}{20}\) \(\cdot\) 3 abz = \(\frac{1}{4}\) abz. Коэффициент: \(\frac{1}{4}\)

Ответ: смотри решение выше