Processing math: 45%
Home / Aptitude Tests / Further Mathematics / Given that \(AB = \b...
Given that AB=(43) and...

Given that AB=(43) and AC=(23), find |BC|.

A.

42

B.

62

C.

210

D.

410

Correct answer is C

BC=BA+AC

Given, AB, then BA=AB

= AB=(43)BA=(43)

= \begin{pmatrix} -2 \\ -6 \end{pmatrix}

|BC| = \sqrt{(-2)^{2} + (-6)^{2}} = \sqrt{40}

= 2\sqrt{10}