Question

Daca x+3y=2y+z=14
Cat este 5x+11y-2z?

Answer 1

x + 3 y = 14 si 2 y + z = 14

5 x + 11 y - 2 z = 42

= 5 x + 15 y - 4 y - 2 z = → l-am scris pe 11 y = 15 y - 4 y

= 5 ( x + 3 y) - 2 ( 2 y + z ) =

= 5 × 14 - 2 × 14 =

= 70 - 28 =

= 42