Hello, Mhmh96!
. . . . . .
Draw diagonal
Triangle is a 3-4-5 right triangle.
We find that and are parallel to
And all the right triangles are similar.
Can you finish the problem?
I'm going to call length , length and .
From the smallest triangles, we can see that by Pythagoras.
We can also see from the larger triangles that
Now note that the area of the largest rectangle is . If we evaluate the area of each smaller piece, we find
Substituting , (since we know ) will enable solving for , which will enable solving for , and finally solving for .
See how you go.