The angle between the diagonals of a quadrilateral formed by the lines `x/a+y/b=1,x/b+y/a=1,x/a+y/b=2 and x/b+y/a=2` is

Prove that the diagonals of the parallelogram formed by the lines x/a +y/b=1,x/b+y/a= 1, x/a + y/b = 2 and x/b + y/a = 2 are at right angles . Also find its area (a != b)

Prove that the diagonals of the parallelogram formed by the four lines : x/a +y/b=1,x/b+y/a= 1, x/a + y/b = -1 and x/b + y/a = -1 are at right angles .

Prove that the parallelogram formed by the lines x/a+y/b=1,x/b+y/a=1,x/a+y/b=2and x/b+y/a=2 is a rhombus.

Prove that the parallelogram formed by the lines x/a+y/b=1,x/b+y/a=1,x/a+y/b=2 and x/b+y/a=2 is a rhombus.

Prove that the parallelogram formed by the lines x/a+y/b=1,x/b+y/a=1,x/a+y/b=2 a n d x/b+y/a=2 is a rhombus.

The angle between the lines x=a and y=b is -

If b gt a , d gt c then are of quadrilateral formed by straight lines x = b, x = a, y = c and y =d is

Prove that the diagonals of the parallelogram formed by the four lines : (x)/(a)+(y)/(b)=1 , (x)/(a)+(y)/(b)=-1 , (x)/(a)-(y)/(b)=1 , (x)/(a)-(y)/(b)=-1 are at right angles.