Question

In fig. AB perpendicular to BC, DC perpendicular to BC and DE perpendicular to AC, prove that
∆CED ~∆ABC
​

Answer 1

Please refer the above photograph for the used process.

KEY POINTS TO REMEMBER :-

☸️ If the SUM OF CO INTERIOR ANGLES is equal to 180 degrees, the lines are said to be parallel.

☸️ CRITERIA FOR SIMILARLITY :-

a) AA Rule :- If the angles of one triangle is equal to the angles of the other triangle, the triangles are said to be similar.

Any two angles must be equal for the two Triangles. If any two angles are equal, The triangles are similar.

REASON :- The sum of the angles of a triangle is constant. Thus, if two angles are equal with another two angles of other triangle, The third angle will be also equal.

b) SAS Rule :- If the ratio of two corresponding sides of two Triangles are equal and the included angle is equal, the triangles are similar.

c) SSS Rule :- If the ratio of all the corresponding sides of the two triangles are equal, The two Triangles are similar.

In the above question, AA Rule is utilised.

Please refer the above photograph....

Thanks!