Multiple Choice

21 • 4

Which is an algebraic expression for 5 more than z?

(1 point)
Responses

5z
5 z

z + 5
z + 5

5z + 5
5 z + 5

5 – z

z + 5

Which word phrase can be used to represent the algebraic expression 4(21 + n)?

(1 point)
Responses

4 plus the sum of 21 and a number n
4 plus the sum of 21 and a number n

4 times the product of 21 and a number n
4 times the product of 21 and a number n

4 times the sum of 21 and a number n
4 times the sum of 21 and a number n

4 less than the sum of 21 and a number n

4 times the sum of 21 and a number n

"8 less than the product of 12 and a number x" can be described by which algebraic expression?

(1 point)
Responses

12x – 8
12 x – 8

8 – 12x
8 – 12 x

12 – 8x
12 – 8 x

8x – 12

12x - 8

Suppose you are building a brick border for a garden by stacking rows of bricks on top of each other. If the height of each brick is 2.5 inches and r represents the number of rows, which algebraic expression would represent the height of the brick wall?

(1 point)
Responses

2.5 + r
2.5 + r

2.5r + r
2.5 r + r

2.5
2.5

2.5r

2.5r

To determine which option is an example of an algebraic expression, let's first understand what an algebraic expression is.

An algebraic expression is a mathematical phrase that contains variables, numbers, and operations. It can be evaluated to obtain a single value. Variables represent unknown values, and operations such as addition (+), subtraction (-), multiplication (•), and division (÷) are used to combine numbers and variables.

Let's analyze each option to find the algebraic expression:

1. 4(3 + 8):
This is an algebraic expression since it contains a variable (4) and the addition operation. It can be simplified by performing the addition within the parentheses: 3 + 8 = 11. Therefore, the expression becomes 4 • 11.

2. 182:
This is not an algebraic expression since it only consists of a single number. It does not contain any variables or operations.

3. 3 – a:
This is an algebraic expression as it contains the variable 'a' and the subtraction operation.

4. 21 • 4:
This is also an algebraic expression involving the multiplication operation. The variable(s) may not be explicitly stated, but it can still be considered an algebraic expression.

Based on the explanations, options 1, 3, and 4 are examples of algebraic expressions.