Question

Реши уравнение (870-?)*2=1400

Answer 1

(870-х)*2=1400
(870-х)=1400:2
870-х=700
х=870-700
х=170

Answer 2

870-?=1400:2
870-?=700
?=870-700
?=170
(870-170)*2=1400
1400=1400