Question

daca a,b,c sunt nr naturale si a+b+c=18 iar2a+b+2c=25 calculati(a+c)×(3a+2b+3c)

Answer 1

a + b + c = 18  

2 a + b + 2 c = 25

( a + a ) + b + ( c + c ) = 25

( a + b + c ) + ( a + c ) = 25

18 + ( a + c ) = 25

a + c = 25 - 18

a + c = 7

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3 a + 2 b + 3 c = (2 a + b + 2 c) +( a + b + c) = 25 + 18 = 43

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( a + c ) × ( 3 a + 2 b + 3 c ) = 7 × 43 = 301