Unit 2 Lesson 1 Congruent Parts, Part 1

When rectangle ABCD is reflected across line EF, the image is DCBA.

How do you know that segment AB is congruent to segment DC?

• A rectangle has 2 pairs of parallel sides.

• Any 2 sides of a rectangle are congruent.

• Congruent parts of congruent figures are corresponding

• Corresponding parts of congruent figures are congruent.

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

Triangle FGH is the image of isosceles triangle FEH after a reflection across line HF.

Select all the statements that are a result of corresponding parts of congruent triangles being congruent.

• EFGH is a rectangle.

• EFGH has 4 congruent sides.

• Diagonal FH bisects angles EFG and EHG

• Diagonal FH is perpendicular to side FE.

• Angle FEH is congruent to angle FGH.

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

CCSS.HSG.CO.B.8

CCSS.HSG.CO.C.10

CCSS.HSG.SRT.B.5

Reflect right triangle ABC across line BC.

Classify triangle ACA′ according to its side lengths. Explain how you know.

Triangle ACA′ must be ​ (a)   . Since a reflection preserves ​ (b)   , side AC is congruent to side ​ (c)   . Since at least ​ (d)   are congruent, triangle ACA′ is isosceles.

• isosceles
• distance
• CA′
• two sides

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

CCSS.HSG.CO.B.8

Select all the statements that must be true.

• Points B, A, and F are collinear.

• Line AD is parallel to line BC.

• Line AD is parallel to line BC.

• The measure of angle CED is the same as the measure of angle FAD

• The measure of angle DAC is the same as the measure of angle BCA

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

CCSS.HSG.CO.B.8

CCSS.HSG.CO.C.10

CCSS.HSG.SRT.B.5

CCSS.HSG.GPE.B.5

CCSS.HSG.SRT.B.4

CCSS.HSG.SRT.A.2

CCSS.HSG.SRT.A.3

Using the triangle congruences, angle BAD ​ (a)   to angle ABC and angle CAE corresponds to ​ (b)   ACB. So the sum of the three angles meeting at ​ (c)   is the same as the sum of the angles in triangle ABC or ​ (d)   . This means that D, A, and E are ​ (e)   .

• corresponds
• angle
• vertex A
• 180 degrees
• collinear

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

CCSS.HSG.CO.B.8

CCSS.HSG.CO.C.10

Using the triangle congruences, angle DAB is ​ (a)   to angle CBA. If two lines are cut by a transversal and ​ (b)   are congruent, then the lines have to be ​ (c)   .

• congruent
• alternate interior angles
• parallel

Tags

CCSS.HSG.CO.B.6

CCSS.HSG.CO.B.7

CCSS.HSG.CO.B.8

CCSS.HSG.CO.C.10

CCSS.HSG.SRT.B.5

CCSS.HSG.GPE.B.5

CCSS.HSG.SRT.B.4