Which of the following graphs best represents the solution to the inequality 4.5x – 10 < 19.25?

A.

Incorrect. The solution to the inequality is x < 6.5. Do values less than 6.5 lie to the left or to the right of 6.5 on a number line? Also, is 6.5 included in the solution set?

B.

Incorrect. The solution to the inequality is x < 6.5. Is 6.5 included in the solution set?

C.

Correct!

D.

Incorrect. The solution to the inequality is x < 6.5. Do values less than 6.5 lie to the left or to the right of 6.5 on a number line?


Which inequality has a solution that is NOT represented by the graph shown?

A. 2x > 22.3
Incorrect. The solution to this inequality is x > 11.15, which is represented in the graph.

B. 3x − 10 > 23.45
Incorrect. The solution to this inequality is x > 11.15, which is represented in the graph.

C. -4x < -44.6
Incorrect. The solution to this inequality is x > 11.15, which is represented in the graph. When dividing by a negative number, the inequality symbol must be reversed in order to preserve the inequality.

D. 5x < 55.75
Correct!


Gracie needs to solve the inequality 4x – 5.5 ≥ 12.5. She decides to use a table to solve the inequality and uses a graphing calculator app to create the table below.

x

y

3

6.5

3.5

8.5

4

10.5

4.5

12.5

5

14.5

5.5

16.5

According to the table, what is the solution to Gracie’s inequality?

A. x > 4.5
Incorrect. The original inequality includes “greater than or equal to,” so the solution needs to include “or equal to” as well.

B. x ≥ 4.5
Correct!

C. x < 4.5
Incorrect. Values of x that are less than 4.5 do not make the original inequality true.

D.  x ≥ 12.5
Incorrect. 12.5 is the y-value that serves as the boundary point for the corresponding x-value of 4.5.


Owen needs to solve the inequality -5(x − 9.2) ≤ 10. Which of the following best represents the solution to this inequality?

A. x ≤ 7.2
Incorrect. When solving the inequality, you must divide by a negative number. Doing so reverses the inequality symbol.

B. x ≥ 7.2
Correct!

C. x ≥ 3.84
Incorrect. When solving the inequality symbolically, don’t forget to distribute the -5 to all terms inside the parentheses.

D. x ≤ 11.2
Incorrect. When solving the inequality symbolically, don’t forget to distribute the negative sign along with the 5 to all terms inside the parentheses. You also divide by a negative number, which reverses the inequality symbol.


Which of the following inequalities could NOT have the solution x > 9?

A. 3(x − 5) < 12
Correct!

B. -2x + 5 < -13
Incorrect. The solution to this inequality is x > 9, because the inequality symbol must be reversed when dividing by a negative number.

C. 7 over 2 7 2 x - 5 > 26 7 over 2 1 2
Incorrect. The solution to this inequality is x > 9.

D. 5 over 2 5 2 (x &minusl 3) > 15
Incorrect. The solution to this inequality is x > 9.