Question

I need help, I know the perimeter of the old one is 21 but I don't know what to do after

Answer 1

If we dilate each side by a factor of 3.4, we have

$\begin{gathered} 6\cdot3.4=20.4 \\ \text{and} \\ 4.5\cdot3.4=15.3 \end{gathered}$

hence, the answer is: