ax2+2hxy+by2=0 represent a homogeneous line. Let the two lines by y=m1x,y=m2x The line y=m1x passes through (2,3) is 3=m1×2⇒m1=
3
2
Thus, the equation of line is 3x−2y=0 Similarly, equation of the second line which passes through (4,5) is 5x−4y=0 Thus, the equation of pair of lines is(5x−4y)(3x−2y)=0 15x2−22xy+8y2=0 Compare it with the given equation a=15,h=−11,b=8 Hence, a+2h+8=15−22+8=1