Question

Teacher gives an activity to the students to measure the height of a traffic light pole. Anup accepts the

challenge as he places a mirror on level ground to determine the height of the pole. He stands on at a

certain distance so that he can see the top of the pole reflected from the mirror. Anup’s eye level from

the base is 1.8 m above the ground. The distance of the Anup and traffic light pole from the mirror are

1.5m and 4.5m respectively, Answer the questions given below (i) Name the two similar triangles formed in the given figure

(a) ∆ ABC ~ ∆ CDE (b) ∆ ACB ~ ∆ CDE (c) ∆ ABC ~ ∆ DEC (d) ∆ BAC ~ ∆ DEC

(ii) State the criteria of similarity that is applicable here

(a) AA Criteria (b) SAS criteria (c) SSS criteria (d) ASA criteria

(iii) Find the height of the pole

(a) 3m (b) 5.4m (c) 6.4m (d) 7.2m

(iv) In ∆ ABC, if ∠ BAC = 50°, then find angle ∠ DCE

(a) 50° (b) 90° (c) 30° (d) 40°

(v) What will be the ratio of areas of ∆ ABC to ∆ DEC

(a) 1 : 9 (b) 9 : 1 (c) 3 : 1 (d) 6:1`​

Answer 1

1) a and 2)c and 3)b and 4)d OR 5)c