Question

sabendo que x=5y+6 determine os valores de x e y nas efuaçoes

2x+y=34


3x-2y=21

Answer 1

2x+y = 34
x = 5y+6
2(5y+6)+y = 34
10y+12+y = 34
11y = 34-12
11y = 22
y = 22/11
y = 2
x = 5*2+6
x = 10+6
x = 16

3x-2y = 21
3(5y+6)-2y = 21
15y+18-2y = 21
15y-2y = 21-18
13y = 3
y = 13/3
x = 5y+6
x = 5*13/3 + 6
x = 65/3 + 6
x = 65/3 + 18/3
x = 83/3