Question

Dacă :
14a-7b= 5 , calculati :
$9b - 18a - \frac{4}{7}$
Mă puteti ajuta ? va rog​

Answer 1

Răspuns:

Explicație pas cu pas:

14 a - 7 b = 5

7 × ( 2 a - b ) = 5

2 a - b = 5/7   l  x ( - 1)  ⇒  b - 2 a = - 5/7

___________________

9 b - 18 a - 4/7 =

9 × ( b - 2 a ) - 4/7 =

= 9 × ( - 5/7 ) - 4/7 =

= - 45/7 - 4/7 =

= - 49/7 =

= - 7

Answer 2

Răspuns:

14a-7b=5

7(2a-b)=5=>2a-b=5/7  I -(1)

b-2a=-5/7

9b-18a-4/7=9(b-2a)-4/7=9·(-5/7)-4/7=-45/7-4/7=-49/7=-7