(X+7)-25=13 198-(x+4)=120 140:(x-8)=7 4 (x+41)=400 11 (x-9)=77 5 (x-9)=350 2x-49=5.3mů2 200-(2x+6)=4mů3

Đáp án:

1. `(x+7)-25=13`

`<=>x+7=38`

`<=>x=31`

2.`198-(x+4)=120`

`<=>x+4=78`

`<=>x=74`

3.`140:(x-8)=7`

`<=>x-8=20`

`<=>x=28`

4.`4 (x+41)=400`

`<=>x+41=100`

`<=>x=59`

5.`11 (x-9)=77`

`<=>x-9=7`

`<=>x=16`

6.`5 (x-9)=350`

`<=>x-9=70`

`<=>x=79`

7.`2x-49=5.3^2`

`<=>2x-49=5.9`

`<=>2x-49=45`

`<=>2x=94`

`<=>x=47`

8.`200-(2x+6)=4^3`

`<=>2x+6=200-4^3`

`<=>2x+6=200-64`

`<=>2x+6=136`

`<=>2x=130`

`<=>x=65`