3.4c: Identifying Similar Trianglesp. 354-361

AA Similarity

• If 2 angles in 1 triangle are congruent to 2 angles in a 2nd triangle, then the 2 triangles

are similar.

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60

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A G

F

R

P B60

50

What do we know?

Are the triangles Similar?If not, why? If so, why? Write a similarity statement.

SSS similarity

• If all 3 ratios of the corresponding sides are equal, then the triangles are similar

• If the ratios are equal, the corresponding sides are proportional Are the Triangles similar?

If not, why not?If so, why? Write a similarity Statement.

SAS similarity

• If 2 sides of the 1st triangle are proportional to 2 sides of a 2nd triangle and the included angles in both triangles are congruent, then the two triangles are similar.

Are the Triangles similar?If not, why not?If so, why? Write a similarity Statement.

examples

10

Hint: when Triangles are overlapping, separate them by re-drawing it

NECAP Released Item

Ex.

• Triangle ABC with A(1,1) B(1,7) C(5,1) and Triangle DEF with D(1,-1) E(3,-1) and F (3,-4).

Are the Triangles similar?If not, why not?If so, why? Write a similarity Statement.

homework