Adding and Subtracting Polynomials Using Algebra Tiles This ...

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Using the first example of adding polynomials from the board, display the algebra tiles
to match the polynomial. As the teacher is working at the overhead, the students are
recreating the polynomial with their set of tiles. The teacher will explain that when
adding and subtracting polynomials, it is easier to use the tiles to model the polynomials
if they arrange the tiles in the same order that the monomials are arranged within each
polynomial. Therefore, arrange the tiles in descending order form left to right on their
2
desks. All the x tiles go on the left, the x tiles go in the middle, and the 1 tiles go on
the right. Show students how the result of the model can show a way to add the
polynomials. Remember to combine like terms and take away zero pairs.
!
!
!
2
3x " 2x + 1
2
x + 4x " 3
(+)
________________
2
4x + 2x " 2
+
!
!
Give students a chance to explore the other example problem with the algebra tiles before
having them work independently on their class work. Demonstrate Example 2 from the
board on the overhead with the tiles. Remember to distribute the negative throughout the
second monomial.
(-)
5x + 4
"2x + 3
!
!
7x + 1
-
!