First slide

Cartesian plane

Question

Area of the triangle formed by the lines y – x = 0, x + y = 0 and y = k in square units is

Moderate

A

2k
B

$k^{2}$
C

$2 k^{2}$
D

$\frac{k^{2}}{2}$

Solution

Vertices of the triangle are (0, 0), (k, k), (– k, k) .
$Area = (\frac{1}{2} [\begin{array}{ccc} 0 & 0 & 1 \\ k & k & 1 \\ - k & k & 1 \end{array}]) = k^{2}$

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