TANGRAM
About TangramTangrams come from China. They are thousands of years old. The Tangram is made by cutting a square into seven pieces. The puzzle lies in using all seven pieces of the Tangram to make birds, houses, boats, people and geometric shapes.In each case you have to use all the seven pieces - no more, no less.Tangrams have fascinated mathematicians and lay people for years. You might be wondering why only the solutions are given. Well, you could just blacken the white lines to create problems! Watch out as Tangrams are known to be addictive.With these Seven Little Wonders the whole family can have hours of fun!
Pola untuk tangram
Pola untuk tangram
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• Dari tangram tersebut buat menjadi bentuk-bentuk yang memungkinkan.
The Algebra Grid
Sumber dari Dr.Cresencia LaguertaAteneo de Naga University Philippines
The Algebra grid visualizes1. Concept of– Algebraic expression– Similar terms
2. Product of– A monomial and binomial– Two binomials with similar terms
3. Factoring/Factorizing a– Product with a common monomial factor (CMF)– Quadratic trinomials
Some preliminary concepts
• Unit of length• Unit of area
Unit of length
xy
a b
Length of segments
xy
x + y 2x
Length of segments
ab
2b + 3a
a + 2b
Unit of area :
• Let and x y
x2 xy
y2
Area of squares
x2 y2
(2x)2
(x+2y)2
Area of rectangels
2x2
3xy (2x2+3xy)
Challenge.
What geometric figure can visualize the following algebraic expressions?• 2x + 3y• 8y2
• 10y2
• 6xy• X+5y• 9xy• 6y+3x
Challenge..
• 4x2 + 2xy• 5xy + 6y2
• X2 +5xy +6y2
• 10y2 + 17xy + 3x2
• 3x2 + 5xy + 2y2
Area of Rectangels
X2 + 2xy+y2 x2 + 4xy+3y2
2x2 + 4xy+4y2
Challenge..
• 4x2 + 2xy• 12 xy+ 6x2
• 4x2 +12xy+9y2
• 10y2 + 17xy+3x2
The Algebra Grid
The Algebra Grid
The Algebra Grid
Uses of the algebra grid
1. Finding product of• a monomial and a binomial– 2x(3x+2y)– 4x(5x-3y)
• Two binomials with similar term– (2x+3y)(4x-2y)– (x+2y)(3x+y)– (x-4)(2x-3y)
….
2. Factorizing/factoring– Polynomial with a common monomial factor• 2xy-3x2
• 6xy + 12 y2
• 5y2 – 15xy– Quadratic trinomial• X2 +5xy+6y2 • 5x2 +11xy+2y2
• X2 – 4xy – 5y2 • 2x2 + 3xy – 2y2
…
3. Proving algebraic identities– (x+y)2 =x2 + 2xy + y2 – (x+y)2 + (x-y)2 =2x2 + 2y2
Example 1
Finding product : 2x (3x + 2y)
Consider :• The factor 2x as the width and 3x+2y as the
length of a rectangle• The product 2x(3x+2y) as the area of the
recangle
Finding product of two polynomials is finding the area of a
rectangle
2x(3x+2y) =
(4x+y)(2x-3y) =
(x-4y)(2x-3y) =
Practice : Product of a monomial and a polynomial
X (x+y) X(x-y) -x(x-y)
2x(x+y) 2x(x-y) -2x(x-y)
3x(2x+5y) 3x(2x-4y) -3x(2x+y)
2x(3x+2y) 2x(3x-2y) -2x(-3x+2y)
5y(2x+3y) 5y(2x-3y) -6y(2x-5y)
Practice : Product of two binomial with similar term
(x+y)(x+2y) (X-y)(x-2y) (x-y)(x+2y)
(2x+2y)(2x+3y) (x-2y)(x-3y) (x+2y)(x-3y)
(2x+3y)(3x+2y) (2x-y)(3x-2y) (2x+y)(3x-2y)
(2x+3y)(3x+4y) (3x-2y)(x-4y) (3x+2y)(x-4y)
(3y+x)(7y+3x) (2x-3y)(3x-4y) (2x-3y)(3x+4y)
Practice
X (x+y) X(x-y) -x(x-y)
2x(x+y) 2x(x-y) -2x(x-y)
3x(2x+5y) 3x(2x-4y) -3x(2x+y)
2x(3x+2y) 2x(3x-2y) -2x(-3x+2y)
5y(2x+3y) 5y(2x-3y) -6y(2x-5y)