Vocabulary and Basics
What symbol means “greater than”?
>
Solve:
x + 5 ≥ 10
x ≥ 5
Solve:
2x + 3 > 9
x > 3
When graphing x < 7, do you use an open or closed circle?
Open circle
A student needs at least 70 points to pass. Let x represent their score. Write an inequality.
x ≥ 70
What symbol means “less than or equal to”?
≤
Solve:
x – 7 < 12
x < 19
Solve:
5x – 7 ≤ 18
x ≤ 5
On a number line, which direction do you shade for x ≥ –3?
Shade right (include –3)
You must be younger than 13 to enter a kid’s contest. Write an inequality for age a.
a < 13
True or False: Inequalities can have more than one solution.
True
Solve:
4x > 20
x > 5
Solve:
3(x – 2) ≥ 9
x ≥ 5
What does a closed circle on –5 mean?
–5 is included in the solution set (closed circle = ≤ or ≥ at –5)
A movie ticket costs $12. You have $50. Write an inequality to show how many tickets t you can buy.
12t ≤ 50
What happens to the inequality sign when you multiply or divide by a negative number?
Reverse (flip) the inequality sign
Solve:
x/3 ≤ 4
x ≤ 12
Solve:
4x + 8 < 2x – 10
x < –9
For x > 2, name a number that is a solution.
A car rental requires you to be 25 or older. Write an inequality for age a.
a ≥ 25
What do we call the set of all possible solutions to an inequality?
The solution set
Solve:
–6 + x ≥ 9
x ≥ 15
Solve:
2 – 5x ≥ 3x – 14
x ≤ 2
For x ≤ –8, name a number that is NOT a solution.
A group needs no more than 120 chairs for an event. Each table seats 6 people. Write an inequality for the number of tables t.
6t ≤ 120 (so t ≤ 20)