Example 1
TLVWKHPLGSRLQWRIWX.,IWT ZKDWLVWX"
Solution
7KHGLDJUDPLQFigure 2.1VKRZVTDVWKHPLGSRLQWRIWKHOLQH
VHJPHQWWX.
The distance WTLVXQLWV,WLVFOHDUIURPWKHSLFWXUHWKDWWKHGLVWDQFHWXPXVWEHXQLWV
Example 2
,QWKHGLDJUDPLQFigure 2.2DQJOHVa and bDUHFRQJUXHQW
6XSSRVHWKDWZHDUHDVNHGWRSURYHWKDWDQJOHVx and y are also
FRQJUXHQW7KDWLV
*LYHQ #ab.
Prove: #xy.
)LOOLQWKHEODQNVRIWKHIROORZLQJOLQHRIUHDVRQLQJ
L #xaEHFDXVH.
LL #ybEHFDXVH.
LLL %HFDXVH#abLWIROORZVWKDW.
Solution
L 9HUWLFDODQJOHWKHRUHP
LL 9HUWLFDODQJOHWKHRUHP
LLL#xy.
WTX
Figure 2.Figure 2.x a b y