Question

Use the diagram. How can you determine BD if you know BC and CD? if you know AB and AD?

Answer 1

http://images.classwell.com/ebooks/images/mcd_geo/mcd_ma_geo_lsn_0395937779_p17_f21.gif

Answer 2

BD = BC + CD
BD = AD - AB

Answer 3

I get it, thank you!

Answer 4

since the points B, C, D are lying on a line
and C is between B and D,

we can use \(\textbf{segment addition postulate}\)

BD = BC + CD

Answer 5

similarly for the second question,

if you know AB and AD :
A, B, D are lying on a line, and B is in-between.

so we can apply \(\textbf{segment addition postulate}\),
AB + BD = AD
=>
BD = AD-AB