The equation of the line passing through the origin and having slopes 3 and −13 is
General eqn. of line passing through origin having slope m,
⇒y=mx
⇒ Eqn. of 1 st line having slope 3 is y=3x
⇒y−3x=0→(1)
Eqn of line having slope −13 is,
=7−13=yx
⇒3y=−x→(1)
⇒3y+x=0→(2)
On multiplying eqn. (1)&(2) we get,
(y−3x)(3y+x)=0
⇒3y2−xy+9xy−3x2=0
=3y2+8xy−3x2=0
If is the required equation of lines.