Question

The opposite vertices of a square are (1, 2) and (3, 8), then the equation of a diagonal of the square passing through the point (1, 2), is.

• A. $3 x - y - 1 = 0$
• B. $3 y - x - 1 = 0$
• C. $3 x + y + 1 = 0$
• D. None of these

Answer 1

Answer: (A)

$3 x - y - 1 = 0$

Answer 2

Slope $= \frac { 8 - 2 } { 3 - 1 } = 3$.

The diagonal is$y - 2 = 3 ( x - 1 ) \Rightarrow 3 x - y - 1 = 0$.