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Question
A straight line AB is 8 cm long. Draw and describe the locus of a point which is:
- always 4 cm from the line AB.
- equidistant from A and B.
Mark the two points X and Y, which are 4 cm from AB and equidistant from A and B. Describe the figure AXBY.
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Solution
Steps of construction:

i. Draw a line segment AB equal to 8 cm.
ii. Draw two parallel lines l and m to AB at a distance of 4 cm.
iii. Draw the perpendicular bisector of AB which intersects the parallel lines l and m at X and Y respectively then, X and Y are the required points.
iv. Join AX, AY, BX and BY.
The figure so formed is a square as its diagonals are equal and intersect at 90°.
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| ii. | ![]() |
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