Question

Tìm số tự nhiên x biết :
a, (4.x+5) :3-121:11=4
b, 131.x-941= 2 mũ 7× 2 mũ 3

giúp vơi ạ.cần gấp hứa tick

Answer 1

`(4x+5):3-121:11=4`

`(4x+5):3-11=4`

`(4x+5):3=4+11`

`(4x+5):3=15`

`4x+5=15xx3`

`4x+5=45`

`4x=45-5`

`4x=40`

`x=40:4`

`x=10`

Vậy `x=10`

________________________

`131x-941=2^7 xx 2^3`

\(131x-941=2^{7+3}\)

`131x-941=2^10`

`131x=2^10 + 941`

`131x= 1024+941`

`131x=1965`

`x=1965:131`

`x=15`

Vậy `x=15`

Answer 2

\(a,\left(4x+5\right):3-11=4\\ \left(4x+5\right):3=15\\ 4x+5=5\\ 4x=0\\ x=0\\ b,131.x-941=128.8\\ 131x-941=1024\\ 131x=1965\\ x=154\\ \)