Transcript Algebra Tiles Practice PowerPoint

Algebra Tiles Practice PowerPoint
Integer Computation
Remember….
• Red Algebra Tiles indicates (-)
• “Zero Pairs” are two matching tiles, one red,
and one another color, that cancel each other
out and equal 0
For example:
Addition of Integers
• Addition can be viewed as “combining”.
• Combining involves the forming and removing
of all zero pairs.
• For each of the given examples, use algebra
tiles to model the addition.
To demonstrate understanding, you may be asked to
use Algebra Tiles to solve a problem in front of
teacher OR draw pictorial diagrams which show the
modeling.
Addition of Integers
(+3) + (+1) =
(-2) + (-1) =
Addition of Integers
(+3) + (-1) =
(+4) + (-4) =
• After students have seen many examples of
addition, have them formulate rules.
Subtraction of Integers
• Subtraction can be interpreted as “take-away.”
• Subtraction can also be thought of as “adding
the opposite.”
• For each of the given examples, use algebra
tiles to model the subtraction.
To demonstrate understanding, you may be asked to
use Algebra Tiles to solve a problem in front of
teacher OR draw pictorial diagrams which show the
modeling.
Subtracting Integers
Rule: Add the opposite.
(+3) – (-5)
(-4) – (+1)
When doing subtraction problems, CHANGE the subtraction sign to an addition
sign. Then “flip” the sign of the number after the new addition sign.
For example: (+3) – (-5) becomes (+3) + (+5)
(-4) – (+1) becomes (-4) + (-1)
Subtracting Integers
(+3) – (-3)
• After students have seen many examples,
have them formulate rules for integer
subtraction.
Multiplication of Integers
• Integer multiplication builds on whole number
multiplication.
• Use concept that the multiplier serves as the “counter”
of sets needed.
• For the given examples, use the algebra tiles to model
the multiplication. Identify the multiplier or counter.
• To demonstrate understanding, you may be asked to use
Algebra Tiles to solve a problem in front of teacher OR draw
pictorial diagrams which show the modeling.
Multiplication of Integers
• The counter indicates how many rows to
make. It has this meaning if it is positive.
(+2)(+3) =
(+3)(-4) =
Multiplication of Integers
• If the counter is negative it will mean “take
the opposite of.” (flip-over)
(-2)(+3)
(-3)(-1)
Division of Integers
• Like multiplication, division relies on the
concept of a counter.
• Divisor serves as counter since it indicates the
number of rows to create.
To demonstrate understanding, you may be
asked to use Algebra Tiles to solve a problem
in front of teacher OR draw pictorial diagrams
which show the modeling.
Division of Integers
(+6)/(+2) =
(-8)/(+2) =
Division of Integers
• A negative divisor will mean “take the
opposite of.” (flip-over)
(+10)/(-2) =
Division of Integers
(-12)/(-3) =
Evaluating Expressions
The green rectangle stands for a
positive variable. Ex : x
The red rectangle stands for a
negative variable. Ex : - x
BE VERY CAREFUL! You cannot think of these rectangles in the same
way you think of C-rods. At this time, try and fit the small yellow
squares into the green rectangle. What do you notice?
Think of these rectangles in terms of quantity, not
size! Remember, you do not know what a variable
stands for. It could be 2, 200, or 2,000,000. You
don’t know until you solve.
Find 2x + 6 if x = 3
How would you build this expression using Algebra Tiles?
+
Find 2x - 4 if x = -2
-
=
12
=0
Practice building and evaluating the
following expressions .
•
•
•
•
3x + 9 if x = 1
5x + 2 if x = (-2)
4x – 4 if x = 3
2x – 3 if x = (-2)