First slide

Equation of line in Straight lines

Question

The straight lines $4 x - 3 y - 5 = 0, x - 2 y = 0$ , $7 x + y - 40 = 0$ and $x + 3 y + 10 = 0$ form

Moderate

A

a rectangle
B

a parallelogram
C

a cyclic quadrilateral
D

none of these

Solution

$\tan A = \frac{\frac{1}{2} + 7}{1 - \frac{7}{2}} = - 3$
$\tan C = \frac{\frac{4}{3} + \frac{1}{3}}{1 - \frac{4}{3} \times \frac{1}{3}} = 3$
$\begin{array}{l} \Rightarrow \tan (A + C) = 0 \\ \Rightarrow A + C = 180^{\circ} \end{array}$
$\Rightarrow A B C D$ is a cyclic quadrilateral.

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App