Question

Determine o conjunto solução do sistema abaixo
{X+y=20
2x-y=4

Answer 1

{x + y = 20 y = 20 - x

{2x - y = 4

2x - (20 - x) = 4

2x - 20 + x = 4

3x - 20 = 4

3x = 4 + 20

3x = 24

x = 24/3

x = 8

y = 20 - 8

y = 12

S = {(x , y) = (8 , 12)}

atte. yrz

Answer 2

Resposta:

S = {8, 12}

Explicação passo a passo:

$\left \{ {{x+y=20} \atop {2x-y=4}} \right. \\\\\\2x-y+x+y=4+20\\\\3x=24\\\\x=\frac{24}{3} \\\\x=8\\\\\\x+y=20\\\\y=20-x\\\\y=20-8\\\\y=12\\\\\\S=\{8,12\}$