例： x − 5 = 31 {\displaystyle x-5=31}
解：
移項，得 x = 31 + 5 {\displaystyle x=31+5}
合併同類項，得 x = 36 {\displaystyle x=36}
即原題目之 36 − 5 = 31 {\displaystyle 36-5=31}
例： 36 x + 11 = 11 x + 36 , 11 x + y = 36 {\displaystyle 36x+11=11x+36 , 11x+y=36}
( 36 − 11 ) x = 36 − 11 = 25 {\displaystyle (36-11)x=36-11=25}
25 x = 25 {\displaystyle 25x=25}
x = 1 {\displaystyle x=1}
11 + y = 36 {\displaystyle 11+y=36}
y = 36 − 11 = 25 {\displaystyle y=36-11=25}
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