Question

A rectangular picture frame, measuring 3.5" high by 5" wide is to be enlarged so that the width is now 9".

Answer 1

Alrighty, so, h=3.5" and w=5" 
The question states that the new width is 9".
5*x=9? 5*1.8=9 (x=1.8)
Multiply the height, 3.5, by 1.8 now. This gives you 6.3"
Perimeter of a rectangle: 2(L+W)
2(6.3+9) ---> 2(15.3) ---> 30.6"

Hope this helps! (: