Question

1)(39+x)-84=78
2)(x-83)+316=425

Answer 1

1. ( 39 + х )- 84 =78
    39 + х - 84 = 78
    х = 78 - 39 + 94
    х = 133
2. (х - 83) + 316 = 425
    х - 83 + 316 = 425
    х = 425 + 83 - 316
    х = 192

Answer 2

спасибо

Answer 3

(39+x)-84=78
39+x=78+84
39+x=162
x=162-39
x=123

(x-83)+316=425
x-83=425-316
x-83=109
x=109+83
x=192