Question

If the equation given by `hxy+10x+6y+4=0` represents a pair of lines, then h is equal to
A. 15
B. 30
C. 5
D. 10

Answer 1

Correct Answer - A
Here , a=0 , b=0 `h=(h)/(2)`, g=5, f=3 and c=4
It represent a pair of lines
`:.|{:( 0, h//2, 5),(h//2,0,3),(5,3,4):}|=0`
`implies 0-(h)/(2)[4(h)/(2)-15]+5[(3h)/( 2)-0]=0`
`implies -h^(2)+(h15)/(2)+(15h)/(2)=0`
`implies h^(2)+15h=0`
`implies h=0,15`