Question

me ajudem nos cálculos por favor
"sistema de equações do 1° grau"

Answer 1

irei usar o método misto

a)
{4x+2y=16
{5x-3y=9

(3){4x+2y=16
(2){5x-3y=9

{12x+6y=48
{10x-6y=18
`````````````````````````
22x=66
x=66/22
x=3

2y=16-4x
2y=16-4*3
2y=4
y=4/2
y=2

sol={(3,2)}

b)
{x-3y=1
{2x+5y=13

(-2){x-3y=1
{2x+5y=13

{-2x+6y=-2
{2x+5y=13
```````````````````````
11y=11
y=11/11
y=1

x=1+3y
x=1+3*1
x=4

sol={(4,1)}

c)
{2x+y=10
{x+3y=15

{-6x-3y=-30
{x+3y=15
````````````````````````
5x=-15
x=-15/5
x=-3

3y=15-x
3y=15-(-3)
3y=15+3
3y=18
y=18/3
y=6

sol={(-3,6)}

bons estudos aí, abraços