Răspuns :
90:(6+x)=10
90:la cat=10
90:9=10
Atunci inseamna ca 6+X=9
X=9-6
X=3
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42:(12-x)=6
42:7=6
Inseamna ca 12-x=7
X=12-7
X=5
42:(12-5)=6
90:la cat=10
90:9=10
Atunci inseamna ca 6+X=9
X=9-6
X=3
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42:(12-x)=6
42:7=6
Inseamna ca 12-x=7
X=12-7
X=5
42:(12-5)=6