Download sr.bincy xavier similar ppt

similar objects

To know the idea of similarity and the
ability to recognize similar objects

To know about the meaning and the
definition of the term similarity.

To understand what are similar triangles.

To know the different properties of similar
triangles and it’s condition to become
similar triangles.
similar objects

Two geometrical objects are called similar if they
both have the same shape, or one has the same
shape as the mirror image of the other.

one can be obtained from the other by
uniformly scaling (enlarging or shrinking), possibly
with additional translation, rotation and reflection.

For example, all circles are similar to each other,

Are Enlargements of each other

Corresponding angles are equal

Sides are related by the same scale factor
100º
are similar if and only if
30º
50º
corresponding
are
congruent
angles
and
the
lengths of corresponding
sides are proportional.
100º
50º
30º
Any triangle is defined by six measures
(three sides, three angles). But you
don't need to know all of them to
show that two triangles are similar.
Various groups of three will do.

Triangles are similar if the measure of all
three interior angles in one triangle are
the same as the corresponding angles in
the other.
Since all three corresponding angles are
equal, we can be sure the triangles are
similar.
Because the triangles are similar, this means
that the three pairs of corresponding sides
are in the same proportion to each other.

But don't forget
Similar triangles can be rotated and/or mirror images of
each other (reflected). In the figure on the right, the two
triangles have all three corresponding sides equal in
length and so are still similar, even though one is the
mirror image of the other and rotated.
Triangles are similar if all three sides in
one triangle are in the same
proportion to the corresponding sides
in the other.

Since all three corresponding sides are
the same length, we can be sure the
triangles are similar.

Because the triangles are similar, this
means that the three angles at P,Q and R
are equal to the angles L,M and N
respectively.

But don't forget
Similar triangles can be rotated and/or mirror images
of each other (reflected). In the figure on the right,
each angle in one triangle is equal to the
corresponding angle in the other, and so are still
similar even though triangle is the mirror image of the
other, rotated and bigger.
Triangles are similar if two sides in one
triangle are in the same proportion to
the corresponding sides in the other,
and the included angle are equal.

The three angles and Since two
corresponding pairs of sides are in the
same proportion, and the included
angles are equal, we can be sure the
triangles are similar.
But don't forget

Similar triangles can be rotated and/or mirror
images of each other (reflected). In the figure on
the right, the two triangles are still similar, even
though one is the mirror image of the other and
rotated.
1.Identify the similar ones?
2.Check whether these triangles are similar?