x=6/2
(1+x)/3=3
x=(2+1)·3
x=(16–1)/3
x=3·3–1
x/3–1=2
x=7–5
x+5=7
7–x=1
x=(5–3)/2
1+3x=16
2x–3=5
x=(5+3)/2
3x=x+6
5–2x=3
x=7–1
