You multiplied binomials by using the FOIL method.

• Find squares of sums and differences.

• Find the product of a sum and a difference.

Square of a Sum• The square of a + b is

o the square of a o plus twice the product of a and b o plus the square of b

o (a + b)2 = (a + b)(a + b) Ex: (x + 4)2 = (x + 4)(x + 4)o = a2 + 2ab + b2 = x2 + 8x + 16

Square of a Difference• The square of a – b is

o the square of a o minus twice the product of a and b o plus the square of b

o (a – b)2 = (a – b)(a – b) Ex: (x – 3)2 = (x – 3)(x – 3)o = a2 – 2ab + b2 = x2 – 6x + 9

Square of a Sum

Find (7z + 2)2.

(a + b)2 = a2 + 2ab + b2 Square of a sum

(7z + 2)2 = (7z)2 + 2(7z)(2) + (2)2 a = 7z and b = 2

= 49z2 + 28z + 4 Simplify.

Answer: 49z2 + 28z + 4

Find (3x + 2)2.

6%

78%

6%11%

A. 9x2 + 4

B. 9x2 + 6x + 4

C. 9x + 4

D. 9x2 + 12x + 4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29

Square of a Difference

Find (3c – 4)2.

(a – b)2 = a2 – 2ab + b2 Square of a difference

(3c – 4)2= (3c)2 – 2(3c)(4) + (4)2 a = 3c and b = 4

= 9c2 – 24c + 16 Simplify.

Answer: 9c2 – 24c + 16

Find (2m – 3)2.

0%

89%

6%6%

A. 4m2 + 9

B. 4m2 – 9

C. 4m2 – 6m + 9

D. 4m2 – 12m + 9

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29

Square of a Difference

GEOMETRY Write an expression that representsthe area of a square that has a side length of 3x + 12 units.

The formula for the area of a square is A = s2.

Answer: The area of the square is 9x2 + 72x + 144 square units.

A = s2 Area of a square

A = (3x + 12)2 s = (3x + 12)

A = (3x)2 + 2(3x)(12) + (12)2 a = 3x and b = 12

A = 9x2 + 72x + 144 Simplify.

GEOMETRY Write an expression that represents the area of a square that has a side length of (3x – 4) units. 78%

0%6%

17%

A. 9x2 – 24x + 16 units2

B. 9x2 + 16 units2

C. 9x2 – 16 units2

D. 9x2 – 12x + 16 units2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29

Product of a Sum and a Difference• The product of a + b and a – b is

o the square of a o minus the square of b

o (a + b)(a – b) = a2 – ab + ab – b2

o = a2 – b2

Product of a Sum and a Difference

Find (9d + 4)(9d – 4).

(a + b)(a – b) = a2 – b2

(9d + 4)(9d – 4) = (9d)2 – (4)2 a = 9d and b = 4

= 81d2 – 16 Simplify.

Answer: 81d2 – 16

Find (3y + 2)(3y – 2).

6%

78%

6%11%

A. 9y2 + 4

B. 6y2 – 4

C. 6y2 + 4

D. 9y2 – 4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29

Assignment• Page 488 – 489• Problems 13 – 39, odds

5 Nykayla Carreras

5 Alexander Vendrell

5 Melanie Vazquez

5 Jason Lowery

5 Jemikah Harrell