Find Dimensions of Rectangular Picture Frame with Increased Area Quadratic Functions

[mustafaazizi]

For those of you who ask why 2Xs You add 2x because if you focus on the original rectangle's length for example, you add 1 x to its left side and 1 x to its right side kind of like so that is 2Xs you added to its length the same goes for its width, you add 1X on the top and 1 X one the bottom.

[kendallrules]

Two identical right triangular pictures whose base measures 12 dm and the height is 8 dm are placed side by side on a rectangular frame that measures 24 dm by 8 dm. Find the area of the frame that is not covered by the picture?