Tìm số nguyên x, biết a) ( x - 5)^2 = 49 b) ( x - 7)^3 = -8

`\bb a)`

`(x-5)^2=49`

`=>(x-5)^2=(+-7)^2`

`**TH1:`

`x-5=7`

`=>x=7+5`

`=>x=12`

`**TH2:`

`x-5=-7`

`=>x=-7+5`

`=>x=-2`

Vậy `x=12` hoặc `x=-2`

$\\$

`\bb b)`

`(x-7)^3=-8`

`=>(x-7)^3=(-2)^3`

`=>x-7=-2`

`=>x=-2+7`

`=>x=5`

Vậy `x=5`