copyright@Ed2netLearning,Inc 1 CONGRUENCE AND SYMMETRY GRADE 3
Dec 17, 2015
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CONGRUENCE AND SYMMETRY
GRADE 3
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Hello, How are you doing?Today, we are going to start a new lesson on
Congruence and Symmetry.
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Congruent FiguresFigures that have the same shape and same
size.Example – Figures given below are
congruent.
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Line of SymmetryA line on which a figure can be folded so
that both sides match.
The given line is line of symmetry.
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Similar FiguresSimilar Figures are figures that have the
same shape but not the same size.
Figures given below are similar.
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Two lines of SymmetryA figure has 2 lines of Symmetry.
Example – A Rectangle can have more than one line of Symmetry.
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Four Lines of Symmetry
Square can have four lines of Symmetry.
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No Line of SymmetrySome Figures have no line of Symmetry.
They cannot be divided into two equal parts.
The Figure has no line of symmetry.
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Draw the line of symmetry of the figure given below.
Answer –
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Tips to RememberTwo triangles are congruent. If the position
of one of the triangle is changed, they are still congruent.
Congruent Figures
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Are the dotted lines Lines of Symmetry of the given figure.
Answer- No
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Are the figure congruent or similar?
Answer- a) Similarb) Neither similar nor congruent
A B
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All the doors of the hall look like each other but are different in size. Which is true about them?
a) They are similarb) They are congruent. c) Either a or bd) None of these
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Draw the lines of symmetry of the given figures.
A B
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ASSESSMENT
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1. Draw the figure that is congruent to the given figure.
Answer-
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2. When the two figures are said to be congruent?a) They have same shapeb) They have same lengthc) They have same shape and sized) None of these
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3. The two lenses in Era’s eyeglasses are circular in shape. They are of the same shape. Are they similar, congruent or both?
Answer - Congruent
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4. Write yes or no to tell if each line is a line of symmetry.
Answer – a) No b) Yes c) No
A B C
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5. Which has only one line of symmetry?
Answer - D
A B C D
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6. Say True or False.a) A Scalene and equilateral triangle are
congruentb) Pentagon can have 3 lines of symmetry.c) Diagonal line of rectangle is a line of
symmetry.Answera) Falseb) Falsec) False
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7. Draw the line of symmetry for the figure given below.
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8. Two triangles are congruent. One triangle has sides of 5 cm, 9 cm and 8 cm. What are the sides of other triangle?Answer- Same sides
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9. How many lines of symmetry do the following figure have?
Answer - 2
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10. Tell whether the figures are congruent or similar.
Answer- a) Congruent b) similar
A B
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Recap Congruent Figures Line of Symmetry Similar Figures One line of symmetry Two and Four Lines of Symmetry Solved Examples Practice Problems
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Good Work!Now Practice worksheets on the Lesson.