If `(a)/(b)=1-(x)/(y)`, then `(b)/(a)=`

The equation to the line passing through the intersection of (x)/(b)+(y)/(b)=1, (x)/(b)+(y)/(a)=1 where ab=a+b and (1, 2) is

Prove that the following sets of three lines are concurrent: (x)/(a)=(y)/(b)=1,(x)/(b)+(y)/(a)=1 and y=x

Show that the tangent of an angle between the lines (x)/(a) + (y)/( b) = 1 and (x)/( a) - (y)/( b) = 1 is (2 ab)/( a^(2) - b^(2) ) .

If theta is the angle between the lines (x)/(a)+(y)/(b)=1,(x)/(b)+(y)/(a)=1, then cos theta

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.

The equations (x)/(a)+(y)/(b)=1 and (x)/(b)+(y)/(a)=1 are inconsistent if

Prove that the parallelogram formed by the straight 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.