Prove that the area of the parallelogram formed by the lines
a1x + b1y + c1 = 0, a1x + b1y + d1 = 0, a2x + b2y + c2 = 0, a2x + b2y + d2 = 0 is sq. units.
Deduce the condition for these lines to form a rhombus.
Given:
The given lines are
a1x + b1y + c1 = 0 … (1)
a1x + b1y + d1 = 0 … (2)
a2x + b2y + c2 = 0 … (3)
a2x + b2y + d2 = 0 … (4)
To prove:
The area of the parallelogram formed by the lines
a1x + b1y + c1 = 0, a1x + b1y + d1 = 0, a2x + b2y + c2 = 0, a2x + b2y + d2 = 0 is sq. units.
Explanation:
The area of the parallelogram formed by the lines a1x + b1y + c1 = 0, a1x + b1y + d1 = 0, a2x + b2y + c2 = 0 and a2x + b2y + d2 = 0 is given below:
Area
∵a1b2 – a2b1
∴ Area
If the given parallelogram is a rhombus, then the distance between the pair of parallel lines are equal.
∴
Hence proved.