(450-500)-x=450
450-500-x=450
50+x=450
x=450-50
x=400
проверка:
(450-500)-400=450
50+400=450
450=450
(450 – 500) - х = 450
-50-х=450
-х=450+50
х=-500
x - (315 - 245) = 526
х-70= 526
х= 526+70
х=596
(859 – 259) :х= 200
600÷х= 200
200х= 600
х=3
