Question

Resolva os sistemas abaixo :

Answer 1

a)


x+y=6
x=6-y

2x-y=-2
2(6-y)-y=-2
12-2y-y=-2
-3y=-14
$y = \frac{14}{3}$
x=6-y

$x = 6 - ( \frac{14}{3} )$
$x = - \frac{84}{3} = - 28$



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

y=5-2(3)
y=5-6
y=-1


x+4y=-1
x+4(5-2x)=-1
x+20-8x=-1
-7x=-21
x=3