Question 32 of 40intermediate🔧 ApplyNumerical2 marks

Solve the inequality: 7≤(3x+11)2≤117 \leq \frac{(3x+11)}{2} \leq 11

Correct Answer

The solution set is x∈[1,113]x \in \left[1, \frac{11}{3}\right].

Exercise: Miscellaneous Exercise on Chapter 5 | Q: 6 | (Page Page 10)
For More Understanding

Explanation

This is a compound inequality (double inequality) of the form a≤3x+112≤ba \leq \frac{3x+11}{2} \leq b. Following the method shown in Example 10 from the Miscellaneous Examples, we solve both inequalities simultaneously by applying the same operation to all three parts. First, multiply by 2 to clear the denominator, then subtract 11, and finally divide by 3 to isolate x. The solution includes all real numbers from 1 to 11/3, inclusive.

Solution Steps

  1. Step 1: Given inequality: 7≤3x+112≤117 \leq \frac{3x+11}{2} \leq 11

  2. Step 2: Multiply all parts by 2: 14≤3x+11≤2214 \leq 3x + 11 \leq 22

  3. Step 3: Subtract 11 from all parts: 3≤3x≤113 \leq 3x \leq 11

  4. Step 4: Divide all parts by 3: 1≤x≤1131 \leq x \leq \frac{11}{3}

  5. Step 5: Solution set: x∈[1,113]x \in \left[1, \frac{11}{3}\right]