2(x²-x)/(x+2)+3(x+2)/(x²-x)=7
(x²-x)/(x+2)=a
2a+3/a=7
2a²-7a+3=0
D=49-24=25
a1=(7-5)/4=1/2⇒(x²-x)(x+2)=1/2
x≠-2
2x²-2x-x-2=0
2x²-3x-2=0
D=9+16=25
x1=(3-5)/4=-1/2
x2=(3+5)/4=2
a2=(7+5)/4=3
⇒(x²-x)/(x+2)=3
x²-x-3x-6=0
x²-4x-6=0
D=16+24=40
x3=(4-2√10)/2=2-√10
x4=2+√10
x1+x2+x3+x4=-1/2+2+2-√10+2+√10=5,5