Question 269822
Assume that the 48 cm^2 is centered in the picture. We get
(i) {{{(20-2x)(12-2x) = 48}}}
foil the left to get
(ii) {{{240 - 64x + 4x^2 = 48}}}
set = 0 and in descending order, we get
(iii) {{{4x^2 - 64x + 192 = 0}}}
factoring, we get
(iv) {{{(x-4)(4x-48) = 0}}}
solving for x, we get
x = 4 
or
x = 12
the dimensions of the inside of the frame are: 4 x 12