6(3х+5у)+7х-5у при х+у＝3

Question

6(3х+5у)+7х-5у при х+у＝3

Answer 1

6(3х+5у)+7х-5у= 18х+30у+7х-5у=25х+25у=25(х+у)

Если х+у=3, то 25*3=75

Answer 2

18x+30y+7x-5y
23x-25y+x+y=3
24x-25y=3