Question

Resolva os sistema

a)x+y=5
x-y=1

b)x-y=1
x+y=9

c)x=2+y
x+y=6

d)y=3+x
x+y=5

e)x-y=2
x+y=12

f)x+y=9
x-y=3

g)x=5-2y
x+3y=10

h)y=3-5x
x+2y=15

i)6x+y=36
x+3y=9

j)x+y=2
6x+2y=10

Answer 1

a)x+y=5
    x-y=1 (Corta os y)
 
 2x=6        x+y=5
  x=6/2      3+y=5
  x= 3         y=5-3
                  y=2


b)x-y=1
   x+y=9  (Corta os y)
 
 2x=10         x+y=9
  x=10/2      5+y=9
  x=5           y=9-5
                   y=4

c)x=2+y
  x+y=6

x+y=6          x=2+y
2+y+y=6      x=2+2
y+y=6-2       x=4
2y=4
y=4/2
y=2


d)y=3+x
   x+y=5

 x+y=5          y=3+x
x+3+x=5       y=3+1
x+x=5-3        y=4
2x=2
x=2/2
x=1