Question

把x2+y2=5 x2-5xy+6y2=0方程组化成两个二元二次方程组是

Answer 1

x-5xy+6y＝0 (x-2y)(x-3y)=0 x=2y或x=3y 1.x=2y x+y+x-11y-2＝0 4y+y+2y-11y-2=0 5y-9y-2=0 (5y+1)(y-2)=0 y=-1/5,y=2 相应的x=-2/5,x=4 2.x=3y x+y+x-11y-2＝0 9y+y+3y-11y-2=0 10y-8y-2=0 5y-4y-1=0 (5y+1)(y-1)=0 y=-1/5或y=1 相应的x=-3/5,x=3 所以 共4组解