Răspuns
Explicație pas cu pas:
6) a) ( x + 3 ) / 5 = ( x + 6 ) / 10
10 ( x + 3 ) = 5 ( x + 6 )
10 x + 30 = 5 x + 30
10 x - 5 x = 30 - 30
5 x = 0 ⇒ x = 0
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b) ( 2 x + 1 ) / 10 = ( 3 x + 1 ) / 14
10 ( 3 x + 1 ) = 14 ( 2 x + 1 ) → produsul mezilor = produsul extremilor
30 x + 10 = 28 x + 14
30 x - 28 x = 14 - 10
2 x = 4
x = 4 : 2
x = 2
Verific:
( 2 × 2 + 1 ) / 10 = ( 3 × 2 + 1 ) / 14
5 / 10 = 7 / 14 = 1 / 2
5 × 14 = 10 x 7
