Question

Solve the compound inequality.3x + 12 ≥ –9 and 9x – 3 ≤ 33 x ≥ –7 and x ≤ –4x ≥ 7 and x ≤ 4x ≥ 1 and x ≤ 4x ≥ –7 and x ≤ 4

Answer 1

To solve this problem, we will solve each inequality for x and the solution to the system will be the intersection of the solution sets.

1) Solving the first inequality for x we get:

$\begin{gathered} 3x+12\ge-9, \\ 3x\ge-9-12, \\ 3x\ge-21, \\ x\ge-\frac{21}{3}, \\ x\ge-7. \end{gathered}$

2) Solving the second inequality for x we get:

$\begin{gathered} 9x-3\le33, \\ 9x\le33+3, \\ 9x\le36, \\ x\le\frac{36}{9}, \\ x\le4. \end{gathered}$

Answer:

$x\ge-7\text{ and x }\le4.$