Congreuncy and Similarites by J Ffryteo

Congreuncy and Similarites

The corresponing vertices must be named in correct order

E.g BCA is congruent to QRP

The hypotenuse and a side of right-angled triangles are equal (RHS)

Two angles and a corresponding side are equal (ASA,AAS,SAA)

All three correspnding sides are equal (SSS)

Two sides and included angle are equal (SAS)

Two figures are similar if

The corresponding angles are equal and

When 2 figures are congruent, they are also similar

However the converse is not true

Similarity and Enlargement

An enlargement is a transformation that changes the size of a figure

If the scale factor is greater than 1, then the image is enlarged

If the scale factor is between o and 1, then the image is reduced

Areas of smilar figures

A1 and A2 denotes the areas of 2 similar figures and l1 and l2 denote their corresponding lengths