Question

Daca a, b, c sunt nr. nat ai a+b+c=18, iar (2a+b+2c)calculati (a+c).(3a+2b+3c).

Dau coroana

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

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