Задача 12186 7a/3c-49^2+9c^2/21ac+3c-49a/7a...

u9450193192

13.12.2016

7a/3c-49^2+9c^2/21ac+3c-49a/7a

SOVA

23.12.2016

★

(7а/3с)–((49а^2 + 9c^2)/21ac)+((3c–49a)/7a) =

=(49a^2/21aс)–((49а^2 + 9c^2)/21ac)+(3c(3c–49a)/21ac)=

=(49a^2–49a^2–9c^2+9c^2–147ac)/21ac=–147ac/21ac=-7