Question

sa se rezolve sostemele de ecuatii: {x
$x { }^{2} - xy - y = 5 \\ 2 x - 3y = 3$

Answer 1

x²-xy-y=5
2x-3y=3
2x=3+3y
x=(3+3y)/2
x²-xy-y=5
(3+3y)²/2²-(3+3y)/2*y-y=5
(9+18y+9y²)/4-(3+3y)/2*y-y=5
(9+18y+9y²)/4-(6+6y)/4*y-y=5
(9+18y+9y²)/4-(6y+6y²)/4-y=5
(9+12y+3y²)/4-y=5
(9+12y+3y²)/4-4y/4=5
(9+8y+3y²)/4=5
(9+8y+3y²)=20
16+8y+3y²=27