Write It!
Write an expression for 5 more than x.
x + 5
3 + 7 = 10
Simplify 2(x + 3)
2x + 6
Simplify 3x + 4x
7x
Are 3x + 2x and 5x equivalent?
Yes, because 3x + 2x simplifies to 5x
A notebook costs $4. Write an expression for the cost of n notebooks.
4n
(Would also accept 4 x n)
Evaluate 4x + 2 when x = 5.
4(5) + 2 = 22
Simplify 4(x + 2)
4x + 8
Simplify 5x + 2 + 3x
8x + 2
Are 2(x + 4) and 2x + 4 equivalent?
No. The first simplifies to 2x + 8
A club charges $8 per member plus a $12 one-time fee. Write an expression for m members.
8m + 12
Evaluate 3x + 6 when x = 4.
3(4) + 6 = 18
Simplify 3(2x + 5)
6x + 15
Simplify 4x + 3 + 2x + 5
6x + 8
Name two expressions equivalent to 4x + 8
Many possible responses. You must prove that your answers simplify to 4x + 8
Examples: 4(x + 2) and 2x + 2x + 8
A student writes 15x + 6 for a $15 starting fee and $6 per month. Explain the mistake.
The starting fee is $15, and that's the constant.
The $6 per month is the rate, so it is the coefficient (the number attached to the variable). The correct answer is 6x + 15
Evaluate 2(x + 5) when x = 3.
2(3 + 5) = 16
Simplify 5(x − 3)
5x - 15
Simplify 8x + 4 − 3x + 2
5x + 6
If you make a table with 2x + 4 and 3x + 1 , they have the same output only one time.
What does x equal when both expressions equal 10?
x = 3
Plan A costs $10 plus $5 per month. Plan B costs $4 plus $7 per month. Write both expressions.
Plan A: 5m + 10
Plan B: 7m + 4
(other variable letters are acceptable)
Evaluate 3(x + 2) + 2x when x = 4.
3(4 + 2) + 2(4) = 26
Simplify 2(3x + 4) + 3(x + 2)
9x + 14
(6x + 8 + 3x + 6 is not a simplified answer)
Simplify 3(x + 4) + 2x + 5
5x + 17
x ?
0 6
1 9
2 12
3 15
Which expression matches the table?
Is it 3x + 6 or 6x + 3
3x + 6