WAEC - Mathematics (2005 - No. 7)
From a point P, R is 5km due west and 12km due south. Find the distance between P and R
5km
12km
13km
17km
คำอธิบาย
\(|PR|^2=|PO|^2+|OR|^2\\
|PR|^2=5^2+12^2\\
|PR|=\sqrt{25+144}=\sqrt{169}=13km\)
\(|PR|^2=|PO|^2+|OR|^2\\
|PR|^2=5^2+12^2\\
|PR|=\sqrt{25+144}=\sqrt{169}=13km\)