Question

Resolva os sistemas:
a)2x+y=9
x-y=-1
b)x+y=32
x-y=2
c)3x-2y=10
x=5y

Answer 1

Resolva os sistemas:

vou usar o método de adição

a)

{2x+y=9
{x-y= -1
------------(+)
3x=8
x=8/3

2x+y=9
2*8/3+y=9
16/3 + y =9
y=9-16/3
y=11/3

b)

{x+y=32
{x-y=2
-----------(+)
2x=34
x=34/2
x=17

x+y=32
17+y=32
y=32-17
y=15

c)

{3x-2y=10
{x=5y

{3x-2y=10
{x-5y=0--->*(-3)

{3x-2y=10
{-3x+15y=0
------------------(+)
0 + 13y=10
y=10/13


x=5*10/13
x=50/13