Download Chapter 2 Section 1

Chapter 2
1.
3c – 4 + 6c – 9
9c – 13
2.
-5(2y – 3) – 7y + 1
-17y +16
3.
8p + 4 – (8p + 15)
-11
4.
7.9y – 0.7 – y + 0.2
6.9y – 0.5
5.
8h + 13h – 6 + 7h2 - h
7h2 + 20h – 6
 Identify terms (like/unlike)
 Combine like terms
 Simplify expressions
A term is a number or the product of a number and
variables raised to powers.
Terms
Coefficient
7
7
5x3
5
‒4xy2
‒4
z2
1
Identify the numerical coefficient of each term.
a. ‒6x The numerical coefficient is ‒6.
b. 27z3 The numerical coefficient is 27.
c. ‒ y
The numerical coefficient is ‒1.
d.
The numerical coefficient is
x
19
1
.
19
Like terms contain the same variables raised to the
same powers. Terms that are not like terms are called
unlike terms.
Cannot do anything with them;
leave them alone
Combining Like Terms
To combine like terms, combine the numerical
coefficients and multiply the result by the
common variable factors.
Add the coefficients,
keep the variables
Determine whether the terms are like or unlike.
a. 6x2, 7x
Unlike terms
b. 19xy, 30xy
Like terms
c. 13xy, –7xy
Like terms
Simplify each expression by combining like terms.
a. 6x2 + 7x2 = 13x2
b. 19xy – 30xy = ‒11xy
c. 13xy2 – 7x2y
Can’t be combined (since the terms
are not like terms)
Find each product by using the distributive property to
remove parentheses.
a. 4(5x + 7) = 4(5x) + 4(7) = 20x + 28
b. ‒3(x + 0.5y – 7) = ‒3(x) + 3(0.5y) – (‒3)(7)
= ‒3x + 1.5y + 21
Simplify each expression.
a. 4(2x + 1) – 8 = 4(2x) + 4(1) – 8
= 8x + 4 – 8
= 8x – 4
b. 8 + 3(3x – 4) = 8 + 9x – 12
= 9x – 4
Write each phrase as an algebraic expression and simplify
if possible. Let x represent the unknown number.
a. Twice a number, plus 9.
2x + 9
b. Seven times the sum of a number and two.
7 · (x + 2) = 7 · x + 7 · 2
= 7x + 14
1.
What are like terms?
2.
How do you combine like terms?
3.
How do we simplify algebraic
expressions?