Q30 of 47 Page 1

Draw a triangle with sides 5cm, 6cm, and 7cm. then draw another triangle whose sides are 4/5 of the corresponding sides of first triangle.


Steps of construction :


1. Draw a line BC = 6 cm


2. Taking B as center and with radius = 5 cm draw an arc.


3. Taking C as center and with radius = 7 cm draw an arc which intersect the previous arc at A.


4. Join AB and AC to get ∆ABC


5. Below BC, make an acute angle ∠CBX


6. Along BX mark 5 ( greater of 4 and 5 in 4/5) points B1, B2, B3, B4 and B5 at equal distances.


7. Join B5C


8. From point B4, make a line B4C' parallel to B5C , meeting BC at C'.[Choosing B4 because we need a 4:5 ratio]


9. From point B' draw a line C'A' parallel to CA.


10. A'BC' is the triangle, whose sides are four - fifth of ∆ABC


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