Question

найдите значение выражения 5х+7х при х=4/7,у=3/5

Answer 1

5x + 7y

$5*frac{4}{7} +7*frac{3}{5}=frac{20}{7}+frac{21}{5}=frac{100+147}{7*5}=frac{247}{35} =7frac{2}{35}$

Answer 2

5*4/7 +7*3/5= 20/7+21/5= 100/35 +147/35= 247/35= 7 2/35