We can divide our birdhouse in 4 rectangles and 2 squares. Each rectangle has measure
and eac square has measure
Then, the total area of our birdhouse is

which gives

the birdhouse has an area:

Now, sinde Erica buy a plywood with dimensions 29x45 in^2, she has

By comparing both numbers, we can see that she have enough wood to make the birdhouse because 1305 in^2 is greater than 406 in^2.