Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Three-dimensional Geometry

Question:

If A= (2, 3), B=(-1, 0), C= (4, 6) then area of the parallelogram ABCD is :

Options:

3

$\frac{3}{2}$

6

2

Correct Answer:

3

Explanation:

The correct answer is Option (1) 3

$\vec{AB}=-3\hat i-3\hat j$

$\vec{BC}=5\hat i+6\hat j$

area = $|\vec{AB}×\vec{BC}|$

so $\vec{AB}×\vec{BC}=\begin{vmatrix}\hat i&\hat j&\hat k\\-3&-3&0\\5&6&0\end{vmatrix}$

$\vec{AB}×\vec{BC}=-3\hat k$

area = 3 sq. units