Question

Реши уравнения.
х+ 7×4 = 40

6×3+х=72

80-х=9×5​

Answer 1

$1) x+7~4=40\\x+28=40\\x+28-28=40-28\\x=40-28\\x=12$

$2) 6~3+x=72\\18+x=72\\18+x-18=72-18\\x=72-18\\x=54$

$3) 80-x=9\cdot \:5\\80-x=45\\80-x-80=45-80\\-x=-35\\x=35$