Question

2x+y=30 10x-y=6 sistema de equações de 1 grau

Answer 1

2x+y=30
10x-y=6

12x-36
x=36:12=3

2.(3)+y=30
6+y=30
y=30-6
y=24

Answer 2

{ 2x + y = 30
{ 10x - y = 6

y = 30 - 2x

10x - y = 6
10x - ( 30 - 2x ) = 6
10x - 30 + 2x = 6
10x + 2x = 6 + 30
12x = 36
x = 36/12
x =  3

y = 30 - 2y
y = 30 - 2 . 3
y = 30 - 6
y = 24

S={( 3 , 24 )}