Question

ME AJUDEM
resolva os sistemas
a) {2x+4y=10
{x-4y=8

B) {3x+7y=40
{-3x+Y=2

c) {2x+4y=20
{X+y=2

D) {-4+Y=-10
{4x+Y=-4

Answer 1

a) {2x+4y=10
    {x-4y=8 
   2x = 18 ==> x = 6

x - 4y = 8==> 4y = x - 8 ==> 4y = 6-8==> 4y= - 2 ==> y = - 2/4

==================================================

B) {3x+7y=40
    {-3x+Y=2
      8y = 42 ==> y = 42/8

3x = y-2==> 3x=42/8-2 ==> 24x = (42-16)==> 24x = 26 ==> x = 26/24

=====================================================
c) {2x+4y=20
    {X+y=2(-2)

 2x + 4y = 20
-2x - 2y = - 4
      2y = 16 ==> y = 8

x = 2 - y ==> x = 2 - 8 ==> x = - 6
=====================================================

D) {-4+Y=-10 ==> y = - 10+4 ==> y = - 6
    {4x+Y=-4
      
  4x = - 4 - y ==> 4x = - 4 -(-6) ==> 4x = - 4+6==> 4x= 2 ==> x = 2/4