Geometrical Construction and Loci

92.
The diagram shows the part of the two houses X and Y and a path P.
Scale 1 cm represents 25 m.
Houses X and Y with path P
A public phone is installed such that it is:
• Less than 125 m from X
• Nearer to Y than X
• More than 100 m from the path
Using ruler and compasses only, find the region where the public phone can be placed. Label it T.
See diagram [4]
Paper 2
93.
The diagram shows triangle RST.
Triangle RST for construction
(a) Measure and write the size of angle RST.
(a) ......................... [1]
(b) Q is the point where the angle bisectors of R, S and T meet. Mark and label the position of the point Q.
(b) See diagram [3]
(c)(i) M is the mid-point of TR and N is the mid-point of RS. Measure the distance, x cm, of line MN from Q.
(c)(i) ......................... cm [1]
(ii) Shade the region that is:
• less than x cm from Q,
• nearer to TR than to TS, and
• nearer to RT than to RS.
(c)(ii) See diagram [2]
Paper 2
94.
Triangle ABC is such that AB = 8 cm, AC = 5 cm and angle BAC = 60°.
AB has already been drawn for you.
Triangle ABC with AB drawn
(a) Construct triangle ABC.
(a) See diagram [2]
(b) Construct the bisector of angle ABC.
(b) See diagram [2]
(c) Write down the length of BC.
(c) BC = ......................... cm [1]
Paper 2
95.
The diagram shows a plan of a triangular plot ABC.
Water pipe runs through point A to C.
Triangular plot ABC with water pipe
(a) Construct locus of all points that are:
(i) Equidistant from B and C,
(a)(i) See diagram [1]
(ii) Equidistant from AB and BC.
(a)(ii) See diagram [2]
(b) A tap T is mounted such that it is:
• Equidistant from AB and BC
• Equidistant from B and C
Label the point where the tap is mounted T.
(b) See diagram [1]
Paper 2
96.
The diagram shows a triangle ABC.
Triangle ABC
(a) Measure angle ACB.
(a) ......................... [1]
(b) The point D is above AC, such that AD is 5 cm and CD is 4 cm. By construction, complete the triangle ADC.
(b) See diagram [2]
(c) The region R lies within the quadrilateral ABCD.
The points in R are:
• nearer to C than A and
• more than 4 cm from B.
By accurate construction, shade the region R.
(c) See diagram [4]
Paper 2
50.
The diagram shows a triangle ABC.
Triangle ABC
(a) Measure and write the length of BC.
......................... cm [1]
(b) (i) By construction, show all the points inside triangle ABC, that are:
(a) 1.5 cm from AC,
(b) Equidistant from C and A.
(ii) Shade the region, inside triangle ABC, of points that are:
• more than 1.5 cm from AC
and
• nearer to C than A
See diagram [6]
Paper 4
51.
The diagram shows a quadrilateral ABCD.
Quadrilateral ABCD
(a) Explain why A, B, C and D lie on a circle.
......................... [1]
(b) Find, by construction, the point O, equidistant from all the vertices.
See diagram [2]
(c) Find, by accurate construction, the region, inside the quadrilateral, containing the points, P such that:
• P lies nearer to CD than DA,
• P lies nearer to CD than CB.
Shade this region.
See diagram [3]
(d) Describe the locus of a point Q, which is equidistant from AB and BC, if Q lies:
(i) On the plane ABCD,
......................... [1]
(ii) In space.
......................... [2]
Paper 4
52.
The diagram shows a map of four villages A, B, C and D.
Map of four villages
(i) Using a scale of 1 cm to represent 2.5 km, make an accurate drawing of the map on the space provided.
CD has been drawn for you.
cd
See diagram [4]
(ii) Measure and write down the size of the angle ABC.
......................... [1]
(iii) Find the actual distance from village B to C.
......................... km [2]
(iv) Describe the locus of all points that are equidistant from C and D.
......................... [2]
(v) Another village E is located on the map such that it is:
(a) 7.5 km away from village B,
(b) equidistant from BC and CD,
(c) closer to A than C.
On your scale drawing, by construction, mark the location of the village E.
See diagram [3]
Paper 4
53.
The diagram represents a triangular field ABC.
Scale: 1 cm to 50 m.
Triangular field ABC
(a) Find the actual distance AB.
......................... m [2]
(b) Construct the locus of all points, inside the field, that are:
(i) 150 m from AB,
(ii) Equidistant from AB and BC.
(c) A tree is to be planted inside the field so that it is:
• Less than 150 m from AB, and
• Closer to BC than to AB.
Shade the possible region in which the tree can be planted.
See diagram [6]
Paper 4