Question

Really need help, please! What is the length of the altitude from D to AB in the parallelogram below?

Answer 1

@tcarroll010 help please?

Answer 2

first, you need to prove triangle(AED) and triangle(DFC) are similar triangles.
According to the definition, to show two triangles are similar, it is sufficient to show that two angles of one triangle are congruent (equal) to two angles of the other triangle.
Since it is a parallelogram, so angle(A) = angle(C), and each trangle has a right angle in it. So similarity is proved.
now, set x=the length you want to find,
two similar triangles have the following relationship:
\[AD/DC=DE/DF\], and we know AD=8, DC=AB=16, DF=10
\[8/16=x/10\]
so, you get x=5

Hope this helps!