Intro to Inequalitie s ≥ ≤ ˂ >
Jan 01, 2016
Intro to Inequalities
≥
≤
˂
>
Credit CardSituation 1: Your mom gave you her credit card
and said that you could go shopping for a birthday present for your girlfriend (or boyfriend). She said that you could spend no more than $125.
1. List at least 5 of the amounts that you could spend.
2. You saw an awesome cell phone that was priced at $130? Can you buy it?
Explain your thinking.
Credit CardSituation 1: Your mom gave you her credit card
and said that you could go shopping for a birthday present for your girlfriend (or boyfriend). She said that you could spend no more than $125.
3. What is the maximum amount that you could spend on the present and still be following your mom's instructions?
4. Is there just one correct amount that you could spend?
Credit CardSituation 1: She said that you could spend no
more than $125.
What other words could we use for this?
Less than or Less than or equal to 125equal to 125
No more No more than 125than 125
Up to 125Up to 125
Maximum Maximum of 125of 125
x ≤ 125
same as
125 ≥ x
Using Inequality symbols helps to represent all the possibilities that you could spend.
Symbolic: spending (x) 125
Credit CardSituation 2: What if your mom said that you had
to spend at least $125 on the present.
1. List no less than 4 of the possibilities that you could spend.
2. What is the least you could spend on the present and still be following your mom's instructions?
3. What is the most you could spend on the present and still be following your mom's instructions?
Credit CardSituation 2: What if your mom said that you
had to spend at least $125 on the present.
What other words could we use for this?
Greater than Greater than or equal to or equal to
125125
At least 125At least 125 125 or more125 or more
Minimum Minimum of 125of 125
x ≥ 125
same as
125 ≤ x
Symbolic: spending (x) 125
Fill in each column with Fill in each column with phrases that best describe phrases that best describe
the inequalitythe inequality
< < << > > >> LESS THAN GREATER
THAN
LESS THAN OR EQUAL TO
GREATER THAN OR EQUAL TO
SMALLER THAN
BIGGER THAN
MAXIMUM OFMINIMUM OF
UP TOAT LEASTNO MORE
THANNO LESS THAN
AT MOST
NAME THAT NUMBERNAME THAT NUMBER
What is a compound inequality? ____________________________
______________________________________________________________________________.
Situation 3: Contestants on American idol must be between the ages of 15 and 28.
1. List at least 5 of the ages a contestant could be.
Situation 3: Contestants on American idol must be between the ages of
15 and 28.
2. What is the youngest you could be and how could you describe that as an inequality?
3. What is the oldest you could be and how could you describe that as an inequality?
4. How could you write this situation using inequalities?
Write inequalities based on the situations below:
1) Jason can spend up to $95 on his Dad’s credit card
2) Ella must have an 85 or over in MMA to get her car back
3) Dana must not fail more than 2 classes this year in order to graduate
4) Sam needs to score better than 98 on his next English quiz to get an A average
5) Angel cannot spend more than 2 and a half hours on her homework
6) John may watch up to half an hour of TV per day
7) If Aaron uses more than 600 minutes on his cell phone each month, he pays a $20 penalty
8) Catherine has to smile 5 or more times a day at work in order to get a $100 bonus
HomeworkHomework
Pg. 171 #1-5, 18-21, 34-37, 46-49Pg. 171 #1-5, 18-21, 34-37, 46-49 Pg. 206 #2, 15, 28, 30-35Pg. 206 #2, 15, 28, 30-35
Inequality symbols allow us to represent situations that have ___________________________.
You use them instead of ___________________________.
What is a solution to an inequality? ___________________________________________________.
Try It1. You can receive a maximum of 3 absences to exempt the final exam.
numbers_______, _______, _______ Inequality____________________
2. Your semester average for the class needs to be at least an 80 to exempt the final exam.
numbers_______, _______, _______ Inequality____________________
3. To pass Algebra you can have no less than a 70 average for the entire school year.
numbers_______, _______, _______ Inequality____________________
4. To ride on the roller coaster, Texas Cyclone, you must be taller than 40 inches.
numbers_______, _______, _______ Inequality____________________