a:=>2x=150
hay x=75
b: =>3x=120
hay x=40
c: =>2x=34
hay x=17
\(2\times x-25=125\)
\(2\times x=125+25\)
\(2\times x=150\)
\(x=150:2\)
\(x=75\)
___________
\(120-3\times x=0\)
\(3\times x=120-0\)
\(3\times x=120\)
\(x=120:3\)
\(x=40\)
_____________
\(2\times x-11=23\)
\(2\times x=23+11\)
\(2\times x=34\)
\(x=34:2\)
\(x=17\)
`2 xx x - 25 = 125`
`=>2xx x=125+25`
`=>2xx x=150`
`=>x=150:2`
`=>x= 75`
`----------`
`120 - 3 xx x = 0`
`=>3 xx x=120-0`
`=>3 xx x=120`
`=>x=120:3`
`=>x=40`
`---------`
`2 xx x - 11 = 23`
`=>2 xx x =23+11`
`=>2 xx x =34`
`=>x=34:2`
`=>x= 17`
\(2\cdot x-25=125\)
\(2x=125+25\)
\(2x=150\)
\(x=150:2\)
\(x=75.\)
\(Vậy...\)
\(120-3\cdot x=0\)
\(-3x=0-120\)
\(-3x=-120\)
\(x=\left(-120\right):\left(-3\right)\)
\(x=40.\)
\(Vậy...\)
\(2\cdot x-11=23\)
\(2x=23+11\)
\(2x=34\)
\(x=34:2\)
\(x=17.\)
\(Vậy...\)
