Question

  cứu mình vs 

Answer 1

a.

$(x-25)-175=0$

$x-25=175+0=175$

$x=175+25=200$

b.

$485-(6x+60)=5$
$6x+60=485-5=480$

$6x=480-60=420$

$x=420:6=70$
c.

$(x-31)-68=0$

$x-31=68+0=68$

$x=68+31=99$

d.

$274-(9x+18)=4$

$9x+18=274-4=270$

$9(x+2)=270$

$x+2=270:9=30$

$x=30-2=28$

Answer 2

e.

$315+(135-x)=450$

$315+135-x=450$

$450-x=450$

$x=450-450=0$

f.

$346+(210-x)=556$

$210-x=556-346=210$

$x=210-210=0$

g.

$442+(420-x)=860$

$442+420-x=860$

$862-x=860$

$x=862-860=2$

h.

$107+(320-x)=317$
$107+320-x=317$
$427-x=317$

$x=427-317=110$