a. 25-(2.x+10)=5
b. 2. 315-(135-x)=215
c. 128+(202-x)=330
d. x-320:32=25.16
e. (x-120).9=450
a. 25-(2.x+10)=5 b. 2. 315-(135-x)=215 c. 128+(202-x)=330 d. x-320:32=25.16 e. (x-120).9=450
By Kennedy
By Kennedy
a. 25-(2.x+10)=5
b. 2. 315-(135-x)=215
c. 128+(202-x)=330
d. x-320:32=25.16
e. (x-120).9=450
`a.25-(2x+10)=5`
`⇒25-2x-10=5`
`⇒-2x+15=5`
`⇒2x=-10`
`⇒x=-5`
Vậy x=-5
`b.2.315-(135-x)=215`
`⇒630-135+x=215`
`⇒x+495=215`
`x=-280`
Vậy x=-280
`c.128+(202-x)=330`
`⇒128+202-x=330`
`⇒330-x=330`
`⇒x=330-330`
`⇒x=0`
Vậy x=0
`d.x-320:32=25.16`
`⇒x-10=400`
`⇒x=410`
Vậy x=410
`e.(x-120).9=450`
`⇒x-120=450:9`
`⇒x-120=50`
`⇒x=170`
Vậy x=170
a. `25“-`(`2`.`x`+`10`)=`5`
( `2` `x` `+` `10`) = `25` `-` `5`
`2` `x` + 10 = 20
`2` `x` = `20` `-` `10`
`2` `x` = `10`
`x` = `10` : `2`
`x` = `5`
b. `2`. `315` `-` (`135` `-` `x`)=`215`
`630` `-` ( `135` `-` `x` ) = `215`
( `135` `-` `x` ) = `630` – `215`
`135` `-` `x` = `415`
`x` = `135` – `415`
`x` = -280
c. 128+(202-x)=330
( 202 – x ) = 330 – 128
202 – x = 202
`x` = 202 – 202
`x` = 0
d. x-320:32=25.16
`x`- 10 = 400
`x` = 400 + 10
`x` = 410
e. (x-120).9=450
( `x` – 120) = 450 : 9
`x` – 120 = 50
`x` = 50 + 120
`x` = 170