

Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
A part of math 123 section 2.7, focusing on solving linear inequalities in one variable. It includes examples and exercises to help students understand the concept. Students are required to define a variable, write an equation/inequality, solve it, and answer the question with a complete sentence.
Typology: Exams
1 / 2
This page cannot be seen from the preview
Don't miss anything!
Math 123 – Section 2.7 – Solving Linear Inequalities – Part II − Page 1
© Copyright 2009 by John Fetcho. All rights reserved
I. When solving word problems, remember to: A. Define a variable for the unknown. B. Write an equation/inequality expressing the situation. C. Solve. D. Answer the question with a complete sentence.
E. Examples - Solve each of the following.
x > 30% (#100)
We want to find all the countries greater than 30%, not included.
Answer: {Netherlands, Denmark}
Answer: {United States, Canada, Norway, Netherlands}
where N is the number of cigarettes consumed, in billions, x years after 1988. Use this formula to solve Exercises 105 – 106.
Describe how many years after 1988 cigarette consumption will be less than 325 billion cigarettes per year. Which years are included in your description? (#106)
Let N = 325 Remember that N is already measured in billions. Let x = The number of years after 1988. So x = 0 means 1988 x = 1 means 1989 x = 2 means 1990 x = 3 means 1991 etc. So x = 17 means 2005
We now need to substitute in for N and write an inequality.
550 – 9x < 325 Subtract 550 from each side to isolate the variable term. −9x < − 225 Divide both sides by −9 to isolate the variable. Remember to switch the inequality sign! x > 25 Add to 1988 to determine the year.
Math 123 – Section 2.7 – Solving Linear Inequalities – Part II − Page 2
© Copyright 2009 by John Fetcho. All rights reserved
1988 + 25 = 2013 Answer the question.
Answer: From 2013 on, cigarette consumption will be less that 325 billion cigarettes per year, in the United States. We won’t talk about the rest of the world!
On this problem, we need to have that the sum of the operator’s weight and the weight of the number of bags of cement has be less than or equal to 2800 pounds. So what don’t we know here? The number of bags of cement, of course! So this tells us what to let our variable represent.
Let x = The number of bags of cement. 65x = The weight of the bags of cement.
265 + 65x < 2800 Subtract 265 from each side to isolate the variable term. 65x < 2535 Divide both sides by 65 to isolate the variable. x < 39 Answer the question.
Answer: The elevator can safely lift 39 bags of cement at one time.
Answer: Inequality: 90 3
86 88 x ≥≥≥≥
; You have to get a 96 on the final to
get an A in the class.