Question

A triangle ABC has been enlarged by scale factor m= 2.5 to the triangle A' B' C'. Calculate the length of AB, if A' B' =6 cm.

• A. 4.4 cm
• B. 3.4 cm
• C. 2.4 cm
• D. 2.1 cm

Answer 1

Answer: (C)

2.4 cm

$△ABC$ is enlarged to $△A^{\prime }{B}^{\prime }{C}^{\prime }$,
Thus, $\frac{A^{\prime }{B}^{\prime }}{AB}=2.5$
$\Rightarrow \frac{6}{AB}=2.5$
$\Rightarrow AB=\frac{6}{2.5}$
$\Rightarrow AB=2.4$ cm