Question

daca a,b,c sunt nr naturale si a+b+c=18iar 2a+b+2c=25

Answer 1

Cerinta:  Sa se calculeze: ( a + c ) × ( 3 a + 2 b + 3 c ).

a + b + c = 18  

2 a + b + 2 c = 25

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

18 + ( a + c ) = 25

a + c = 25 - 18

a + c = 7

______________________

( a + c ) × ( 3 a + 2 b + 3 c ) = 301

= 7 × [ ( a + b + c ) + ( 2 a + b + 2 c ) ] =

= 7 × ( 18 + 25 ) =

= 7 × 43 =

= 301