Inequalities: Understanding inequality

Examples with solutions for Inequalities: Understanding inequality

Exercise #1

Which diagram represents the solution to the inequality below?

5-8x<7x+3

Video Solution

Step-by-Step Solution

First, we will move the elements:

5-8x>7x+3

5-3>7x+8x
2>15x

We divide the answer by 13, and we get:

x > \frac{2}{15}

Answer

Exercise #2

What is the solution to the inequality shown in the diagram?

-43

Video Solution

Step-by-Step Solution

The task is to interpret the inequality shown by a number line diagram.

First, observe the number line diagram provided. The numbers -4 and 3 are highlighted with vertical dashed lines. A critical point is at 3, where the circle is filled, indicating the inclusion of this point in the set. The line then extends from 3 to the right, suggesting that any point greater than or equal to 3 is included.

This indicates the inequality for x x is x3 x \geq 3 . The filled circle means 3 itself is part of the solution.

Thus, the solution to the inequality represented by the diagram is:

3x 3 \leq x

This matches with choice number 3 in the provided options: 3x 3 ≤ x .

Answer

3x 3 ≤ x

Exercise #3

What is the solution to the following inequality?

10x43x8 10x-4≤-3x-8

Video Solution

Step-by-Step Solution

In the exercise, we have an inequality equation.

We treat the inequality as an equation with the sign -=,

And we only refer to it if we need to multiply or divide by 0.

 10x43x8 10x-4 ≤ -3x-8

We start by organizing the sections:

10x+3x48 10x+3x-4 ≤ -8

13x48 13x-4 ≤ -8

13x4 13x ≤ -4

Divide by 13 to isolate the X

x413 x≤-\frac{4}{13}

Let's look again at the options we were asked about:

Answer A is with different data and therefore was rejected.

Answer C shows a case where X is greater than413 -\frac{4}{13} , although we know it is small, so it is rejected.

Answer D shows a case (according to the white circle) where X is not equal to413 -\frac{4}{13} , and only smaller than it. We know it must be large and equal, so this answer is rejected.

 

Therefore, answer B is the correct one!

Answer

Exercise #4

Which inequality is represented by the numerical axis below?

-7-20

Video Solution

Step-by-Step Solution

To solve the problem and determine the inequality represented by the number line, follow these steps:

  • Examine the endpoints of the interval on the number line. At 7-7, there is an open circle, indicating that 7-7 is not included in the interval.
  • At 00, there is a closed circle, indicating that 00 is included in the interval.
  • This gives us the inequality for the interval: open at 7-7 (<<) and closed at 00 (\leq).

Therefore, the inequality represented by the number line is 7<x0 -7 < x \leq 0 .

This is consistent with option 1 in the provided choices. The inequality is represented by 7<x0-7 < x \leq 0.

Answer

-7 < x ≤2

Exercise #5

Which diagram corresponds to the inequality below?

40x+575x1325x+7 40x+57≤5x-13≤25x+7

What is its solution?

Video Solution

Step-by-Step Solution

To solve the compound inequality 40x+575x1325x+7 40x + 57 \leq 5x - 13 \leq 25x + 7 , we first break it down into two inequalities and solve them separately.

Step 1: Solve the inequality 40x+575x13 40x + 57 \leq 5x - 13 .

Subtract 5x 5x from both sides: 40x5x+5713 40x - 5x + 57 \leq -13 .

This simplifies to 35x+5713 35x + 57 \leq -13 .

Subtract 57 from both sides to isolate the term with x x : 35x70 35x \leq -70 .

Divide by 35 to solve for x x : x2 x \leq -2 .

Step 2: Solve the inequality 5x1325x+7 5x - 13 \leq 25x + 7 .

Subtract 5x 5x from both sides: 1320x+7 -13 \leq 20x + 7 .

Subtract 7 from both sides to isolate the term with x x : 2020x -20 \leq 20x .

Divide by 20 to solve for x x : 1x -1 \leq x .

Step 3: Determine the solution by finding the intersection of the two solutions.

The first solution is x2 x \leq -2 and the second solution is 1x -1 \leq x .

There is no overlap between x2 x \leq -2 and 1x -1 \leq x . Therefore, there is no value for x x that satisfies both conditions simultaneously.

Therefore, the solution is "No solution."

The correct diagram corresponds to choice 1, which indicates a solution of "No solution."

Answer

-2-1

No solution.