=5x−6y+2f [∵(−1,−1) is the point in intersection ] ⇒‌‌4×(−1)−5×1+2g=0 ⇒‌‌2g=9 ‌ and ‌‌5×(−1)−6×(−1)+2f=0 ‌2f=−1 ‌g+f=4 Also, ( −1,−1 ) will satisfy ‌2x2+5xy−3y2+2gx+2fy+c=0 ‌⇒‌‌2+5−3−2g−2f+c=0 ‌⇒‌‌4−8+c=0 ‌‌‌‌‌c=4 ‌‌‌g+f=c
