Answer:
7.9
Step-by-step explanation:
the first thing to do is find the second projection.
16-7 = 9
than we can use a proportion to find BD
7 : BD = BD : 9
BD = √9 x 7 = √63 = 7.9
we have to use the square root because in the proportion BD Is repeated two times. If we don’t use it, we find BD^2
