The area of the triangle formed by the lines $x = 0, y = 0$ and $\frac{x}{a} + \frac{y}{b} = 1$ is

If the sum of the distances of a point from two perpendicular lines in a plane is $1$,then its locus is

Without using the distance formula,show that the points $(-2,-1), (4,0), (3,3),$ and $(-3,2)$ are the vertices of a parallelogram.

Two sides of a rhombus are along the lines $x-y+1=0$ and $7x-y-5=0$. If its diagonals intersect at $(-1,-2)$,then one of the vertices of this rhombus is

The equations of sides $AB$,$BC$,and $CA$ of a $\triangle ABC$ are $2x+y=0$,$x+py=q$,and $x-y=3$ respectively. If $P(2,3)$ is its orthocenter,then the value of $p+q$ equals

The incentre of the triangle formed by the lines $x+y=1$,$x=1$,and $y=1$ is