Răspuns:
(a + c) × (3a + 2b + 3c) = 32 × 82 = 2624
Explicație pas cu pas:
a + b + c = 25
2a + b + 2c = 57
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(a+c)×(3a+2b+3c)=?
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2a + b + 2c - (a + b + c) = 57 - 25
2a + b + 2c - a - b - c = 32
a + c = 32
2a + b + 2c + a + b + c = 57 + 25
3a + 2b + 3c = 82
(a + c) × (3a + 2b + 3c) = 32 × 82 = 2624
Succes!
