Răspuns:
Explicație pas cu pas:
a × ( b + 5 ) = 336
a × b + 5 × a = 336
301 + 5 × a = 336
5 × a = 336 - 301
5 × a = 35
a = 35 : 5
a = 7
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c × ( 3 + d ) = 140 si c × d = 125
3 × c + c × d = 140
3 × c + 125 = 140
3 × c = 140 - 125
3 × c = 15
c = 15 : 3
c = 5