Question

{3x + y=5
{X-2y=7
Am si eu nevoie de ajutor pt sistemult acesta de substitutie,va rog frumos!

Answer 1

3x+y = 5

x-2y = 7

y= 5-3x

x-2y = 7

y=5-3x

x-2(5-3x) = 7

y=5-3x

x-10+6x= 7

y=5-3x

7x =17

y= 5-3x => y= 5-3*17/7 = 5-41/7 amplifici pe 5 cu 7

x= 17/7

y = 35/7-41/7  = -6/7

x= 17/7