3х•78+15=60
3х•93=60
3х=93-60
3х=33
Х=33÷3
Х=11
Пошаговое объяснение:
3( х + 26) +15= 60
3(x + 26) = 60 - 15
3(x + 26) = 45
x + 26 = 45:3
x+26 = 15
x = 15 - 26
x = -9
3( х - 26) +15= 60
3(x - 26) = 60 - 15
3(x - 26) = 45
x - 26 = 45:3
x - 26 = 15
x = 15 + 26
x = 41
3х•78+15=60
3х•93=60
3х=93-60
3х=33
Х=33÷3
Х=11
Пошаговое объяснение:
3( х + 26) +15= 60
3(x + 26) = 60 - 15
3(x + 26) = 45
x + 26 = 45:3
x+26 = 15
x = 15 - 26
x = -9
3( х - 26) +15= 60
3(x - 26) = 60 - 15
3(x - 26) = 45
x - 26 = 45:3
x - 26 = 15
x = 15 + 26
x = 41