GB-37-04-001 · Circle locus
A plan uses scale 1 cm represents 15 m. A point P represents a tree. Draw on plain paper the locus of points 99 m from the tree. State the radius used on the plan.
Loci: Fixed Distance from a Point
Supplementary GCSE method — not covered in this booklet
Method
1) Divide actual distance by scale to find plan radius in cm
2) Locus of points at a fixed distance from P is a circle centred at P
Worked Example (GB-37-04-001)
1)
Plan radius = 99 ÷ 15.
2)
Circle centred at P with radius 6.6 cm.
Ans =
Circle centred at P of radius 6.6 cm.