Question

3 скриншота,решите пожалуйста.

Answer 1

$1)\frac{21z}{11} *\frac{1}{15z} =\frac{7}{11} *\frac{1}{5} =\frac{7}{55} \\2)\frac{4k+4y}{24}:\frac{k^{2} +ky}{30k^{2} }=\frac{4(k+y)}{24} :\frac{30k^{2} }{k^{2} +ky} =\frac{4(k+y)}{4} *\frac{5k^{2} }{k(k+y)} =5k\\3)(\frac{2a^{7} }{z^{2} } )^{3} *(\frac{z^{3} }{5a^{2} } )^{2} =\frac{8a^{21} }{z^{6} } *\frac{z^{6} }{25a^{4} } =8a^{17} *\frac{1}{25} =\frac{8}{25} a^{17}$