Congruent Triangles

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Congruent Triangles

HLIsosceles/ Equilateral

Triangles

Isosceles/ Equilateral

Triangles

CPCTC

Prove.Given: and

Prove:

Q T QR TR

PR SR

Given:

Prove:

AB ACBAD CADAD bisects BC

Explain how you can use SSS, SAS, ASA, or AAS with CPCTC to prove that D B

Explain how you can use SSS, SAS, ASA, or AAS with CPCTC to complete a proof.

Given:

Prove:

CB CD, BCA DCA

BA DA

Find the values of x and y.

What is the measure of a base angle of an isosceles triangle if the vertex angle measures 38° and the two congruent sides each measure 21 units?

What is the measure of the vertex angle of an isosceles triangle if one of its base angles measures 42°?

Use the information in the figure. Find mD.

Find the value of x. The diagram is not to scale.

Find the value of x. The diagram is not to scale.

Given: RS ST , mRST 3x 48mSTU 9x

The sides of an isosceles triangle have lengths , . The base has length . What is the length of the base?

2x 4 x 85x 2

For which situation could you prove using the HL Theorem?

1 2

What additional information will allow you to prove the triangles congruent by the HL Theorem?

Is by HL? If so, name the legs that allow the use of HL.

PQS RQS

Is there enough information to conclude that the two triangles are congruent? If so, what is a correct congruence statement?

Complete the statement . Explain why it is true.

BF ?