Q.
If x1,y1 are the roots of x2+8x−20=0,x2,y2 are the roots of 4x2+32x−57=0 and x3,y3 are the roots of 9x2+72x−112=0, then the points (x1,y1),(x2,y2) and (x3,y3) :
Given x1+y1=−8⇒y1=−8−x1; x2+y2=−8⇒y2=−8−x2 x3+y3=−8⇒y3=−8−x3 and
Now check ∣∣x1x2x3−8−x1−8−x2−8−x3111∣∣ value of this determinant comes out to be zero.