Big Ideas Math Algebra 1, 2015
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Big Ideas Math Algebra 1, 2015 View details
6. Solving Absolute Value Inequalities
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Exercise 11 Page 91

Create an or compound inequality because the absolute value is greater than or equal to the given value.

Solution Set: t≤ -2/3 or t≥3
Graph:

Practice makes perfect
We are asked to find and graph the solution set for all possible values of t in the given inequality. |6t-7|-8≥ 3 To do this, let's isolate absolute value expression first.
|6t-7|-8≥ 3
|6t-7|≥ 11

Now, we will create a compound inequality by removing the absolute value. In this case, the solution set is any number with a distance greater than or equal to 11 away from the midpoint in the positive direction or a distance greater than or equal to 11 away from the midpoint in the negative direction. 6t-7 ≥ 11 or 6t-7≤ - 11 Let's isolate t in both of these cases before graphing the solution set.

Case 1

We can solve the inequality by performing inverse operations on both sides of the inequality. Let's solve the first case.
6t-7 ≥ 11
6t≥ 18
t ≥ 3
This inequality tells us that all values greater than or equal to 3 will satisfy the inequality.

Case 2

Now, let's solve the second case of the inequality.
6t-7≤ - 11
6t≤ -4
t≤ -4/6
t≤ -2/3
This inequality tells us that all values less than or equal to - 23 will satisfy the inequality.

Solution Set

The solution to this type of compound inequality is the combination of the solution sets. First Solution Set:& t≥ 3 Second Solution Set:& t≤ - 23 Combined Solution Set:& t≤ - 23 or t≥ 3

Graph

The graph of this inequality includes all values less than or equal to - 23 or greater than or equal to 3. We show this by keeping the endpoints closed.