Lesson 1.5 Distributive Property

download report

Transcript Lesson 1.5 Distributive Property

Objective
The student will be able to:
use the distributive property to
simplify expressions.
PFA 8
Designed by Skip Tyler, Varina High School and Nicole Kessinger, Deep Run High School
Edited by Dave Wesley Crestwood Middle School
The Distributive Property
The process of distributing the number
on the outside of the parentheses to
each term on the inside.
a(b + c) = ab + ac and (b + c) a = ba + ca
a(b - c) = ab - ac and (b - c) a = ba - ca
Example #1
5(x + 7)
5•x+5•7
5x + 35
Example #2
3(m - 4)
3•m-3•4
3m - 12
Example #3
-2(y + 3)
-2 • y + (-2) • 3
-2y + (-6)
-2y - 6
Which statement demonstrates the
distributive property incorrectly?
1.
2.
3.
4.
3(x + y + z) = 3x + 3y + 3z
(a + b) c = ac + bc
5(2 + 3x) = 10 + 3x
6(3k - 4) = 18k - 24
Answer Now
A term is a
1) number,
2) variable, or
3) a product / quotient of numbers
and variables.
Example
5
m
2x2
The coefficient is
the numerical part of the term.
Examples
1) 4a
4
2) y2
1
2
5x
3)
7
5
7
Like Terms are terms with the same
variable AND exponent.
To simplify expressions with like
terms, simply combine the like
terms.
Are these like terms?
1) 13k, 22k
Yes, the variables are the same.
2) 5ab, 4ba
Yes, the order of the variables
doesn’t matter.
3) x3y, xy3
No, the exponents are on different
variables.
Which of the following is the simplified
form of
-4x + 7x ?
1.
2.
3.
4.
-4
3x
-3x
4
Answer Now
2
2
8x  2x  5a  a
2
8x and 2x
5a and a
2
are like terms
are like terms
The above expression simplifies to:
2
10x  6a
Simplify
1) 5a + 7a
12a
2) 6.1y - 3.2y
2.9y
3) 4x2y + x2y
5x2y
4) 3m2n + 10mn2 + 7m2n - 4mn2
10m2n + 6mn2
5) 13a + 8a + 6b
21a + 6b
6) 4d + 6a2 - d + 12a2
18a2 + 3d
3y
y
7)

4 4
y
3y 1y
4y


 1y
4
4
4
Which of the following is the simplified
form of
5x - 4 - 7x + 14 ?
1.
2.
3.
4.
-12x + 10
-2x + 10
2x - 18
12x – 18
Answer Now
If a triangle has sides 3x - 2, 5 - x and 2x - 5,
what is the perimeter of the triangle?
1.
2.
3.
4.
4x - 2
4x + 2
5x - 2
5x - 7
Answer Now
Which figure below models the simplification
of - 4x - 5 + 7x + 7 using these tiles?
1.
2.
3.
4.
Answer Now
Bonus! Which of the following is the
simplified form of a + 3a - 4(9 - a) ?
1.
2.
3.
4.
-36
3a - 36
8a - 36
8a + 36
Answer Now
Homework
Page 30 # 21 - 41odds
(don’t forget #34)
and # 50 - 60 all