T
H
E

E
L
E
M
E
N
T
S
Book II   Proposition 5
Then, since
    the complement CH is equal to the complement HF, [I.43]
    let DM be added to each;
therefore
    the whole CM is equal to the whole DF.

But
    CM is equal to AL,
since
    AC is also equal to CB;
therefore
    AL is also equal to DF.
Previous Page    Return to Propositions    Next Page