156-(x+61)=80
x+61 =156-80
x+61=76
x =76-61
x =15
156-(x+61)=80
=>x+61=156-80
=>x+61=76
=>x=76-61
=>x=15
=>(x+61)=156-80
=>(x+61)=76
=>x=76-61
=>76-61
=>x=15
156-(x+61)=80
x+61 =156-80
x+61 =76
x =76-61
x =15
k mik mik k lại
156-(x+61)=80
x+61=156-80
x+61=76
x=76-61
x=15