5+(7х-12)/3=х+13 14(2х-3)-5(х+4)=2(3х+5)+5х - вопрос №860663657123131423542355 от dpoarkov56 13.04.2020 01:34

Question

Математика: 5+(7х-12)/3=х+13 14(2х-3)-5(х+4)=2(3х+5)+5х

dpoarkov56 · Answer

(7x-12)/3=x+13-5; (7x-12)/3=x+8; (7x-12)/3*3=(x+8)*3; 7x-12=3x+24; 7x-3x=24+12; 4x=36; x=36/4; x=9
14(2х-3)-5(х+4)=2(3х+5)+5х; (28x-42)-(5x+20)=6x+10+5x; 28x-42-5x-20=11x+10;23x-62=11x+10; 23x-11x=10+62; 12x=72; x=72/12; x=6