Question

One diagonal of a square is 3x-4y+8=0 and one vertex is (-1,1), then the area of square is

A. `(1)/(50)"sq.unit"`
B. `(1)/(25)"sq.unit"`
C. `(3)/(50)"sq.unit"`
D. `(2)/(25)"sq.unit"`

Answer 1

Correct Answer - D
Let ABCD be square having vertex A(-1, 1).
One diagonal is 3x-4y+8=0, clearly, it is BD.
Let O be centre of the square.
`therefore OA=OB=|(-3-4+8)/(5)|=(1)/(5)`
`"Area of square" = 4 xx DeltaAOB``=4((1)/(2) xx OA xx OB)=4((1)/(2) xx (1)/(5) xx (1)/(5)) = (2)/(25)` sq. unit