Răspuns :
c)b=a+2
a=b-2
b=c:2
c=2b
a+b+c=66
b-2+b+2b=66
4b=68
b=17
a=15
c=2×17=34
d)a=b:7
b=7a
b=c-123
a+b+c=1623
a+7a+7a+123=1623
15a=1623-123
15a=1500
a=100
b=700
c=700+123=823
e)a=b:4
b=4a
a=c:2
c=2a
b=c+30
4a=2a+30
2a=30
a=15
b=4×15
b=60
c=2×15
c=30
a=b-2
b=c:2
c=2b
a+b+c=66
b-2+b+2b=66
4b=68
b=17
a=15
c=2×17=34
d)a=b:7
b=7a
b=c-123
a+b+c=1623
a+7a+7a+123=1623
15a=1623-123
15a=1500
a=100
b=700
c=700+123=823
e)a=b:4
b=4a
a=c:2
c=2a
b=c+30
4a=2a+30
2a=30
a=15
b=4×15
b=60
c=2×15
c=30
Adaug o rezolvare figurativa !
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