Question

determine o valor de x elevado a 3 ,menos y elevado a 3 no sistema {2 (x-1=3 (y+1) {x-3y=y+5

Answer 1

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

2(x-1=3y+3)
2x-2=6y+6
2x-6y= 6+2
2x-6y= 8

x-3y=y+5
x-3y-y=5
x-4y=5

2x-6y=8
x-4y=5 

x=5+4y
2x-6y=8
2.(5+4y)-6y=8
10+8y-6y=8
2y=-2
y=-2/2
y= -1

x=5+4y
x=5+4.(-1)
x=5-4
x=1

x^3-y^3=
1^3-(-1^3)=
1+1=
2