Question

Solve for x and y
2 + y= -2x

-2x2+ 8xy + 42= y

Answer 1

`\\ \sf\longmapsto 2+y=-2x---(1)`

`\\ \sf\longmapsto -2x^2+8xy+42=y\dots(2)`

From equation (1)

`\\ \sf\longmapsto y=-2x-2\dots(3)`

Put in eq(2)

`\\ \sf\longmapsto -2x^2+8x(-2x-2)+42=-2x-2`

`\\ \sf\longmapsto -2x^2-16x^2-16x+42=-2x-2`

`\\ \sf\longmapsto -18x^2-16x+2x+42+2=0`

`\\ \sf\longmapsto -18x^2-14x+44=0`

On solving

`\\ \sf\longmapsto x=(11)/(9)\:or\;-2`

Take it whole.

• x=-2

Put in eq(3)

`\\ \sf\longmapsto y=-2(-2)-2=4-2=2`

Hence

• (x,y)=(-2,2)