Question

resolva os sistemas..

a) 2x+y=5
x-2y=5

b) x+2y=1
2x+3y=0

Answer 1

Qualquer coisa, peça. Valeu

Answer 2

2x+y=5
y= 5 - 2x

x-2y=5
x-2*(5-2x) = 5
x-10 + 4x = 5
5x = 10+5
x=15/5 = 3

y=5-2*3
y=-1

b)x+2y=1
x=1-2y

2x+3y=0
2*(1-2y)+3y=0
2-4y+3y=0
-y=-2
y=2

x=1-2*2
x=-3