Math 10 online work that was due today at the start of class: Gateway Homework #1 (turn in worksheet now, while I take roll) Section 1.4/1.5 Online Homework

Quiz coming up week after next: Gateway Quiz Try #1 8 questions Online quiz with paper worksheet no calculator Worth 80 points (only your best score of the semester counts) You have had a number of practice Gateway questions mixed in with your regular homework assignments, but you should also take Practice Gateway Quiz 1 before the next class session: 8 questions on the practice Gateway, same type as on the actual Gateway You can take the practice Gateway as many times as you want, and only your best score counts for points. Additional paper versions of practice Gateways can be picked up in the open lab from any TA or teacher. REMEMBER: Gateway study help available every MTWTh in Room 203 JHSW.

Quiz coming up the class session after Gateway Quiz 1 on sections 1.2 through 1.8 15 questions; 50 minute time limit Taken in class, but via the online course web site Worth 60 points 1 attempt No calculators allowed Practice Quiz 1 should be taken at least 2-3 times before the quiz day: 19 questions; 50 minute time limit; can take it anywhere Worth 10 points Unlimited attempts, only best score counts Each time you take it, you will get a different set of questions, so the more times you take it, the more chances you’ll have of seeing all the types of questions that might be on the real quiz. Don’t use a calculator, since you can’t on the real quiz. REMEMBER: Come to the open lab in 203 if you need help. M – Th.

Any questions on today’s homework. (Sections 1. 4/1 Any questions on today’s homework? (Sections 1.4/1.5) Reminder: You should be doing this homework without using a calculator, because calculators can’t be used for Quizzes 1 or 2 or the Gateway Quiz.

CLOSE Please YOUR LAPTOPS, and get out your note-taking materials. and turn off and put away your cell phones, and get out your note-taking materials.

Section 1.6 Subtracting real numbers Example Substitute the opposite of the number being subtracted Then add a – b = a + (-b) Example Subtract the following numbers. (-5) – 6 – (-3) = (-5) + (-6) + 3 = -8

Example from homework: Subtract. −2−(−2) Answer: 0

More on subtracting real numbers: Example: “Subtract -5 from 8” Write the 8 FIRST, then subtract -5 FROM the 8. 8 – (-5) = 8 + 5 = 13 Example: “Decrease -8 by 15” This time you start with -8 and then subtract 15. -8 – 15 = -23 Example: -6 – (2 - 11) Do the part in parentheses first : 2 – 11 = -9 Now rewrite the problem as: -6 – (-9) = -6 + 9 = 3

Note: You may find the number line worksheets handed out at the last class session useful for completing these kinds of problems.

Example from homework: Subtract 10 from -5. Answer: -15

Evaluating algebraic expressions: Example: Evaluate x – y when x = -5 and y = 4 Plug in -5 in place of the x and 4 in place of y: -5 – 4 = -9

Example from homework A commercial jet liner hits an air pocket and drops 259 feet. After climbing 141 feet, it drops another 147 feet. What is its overall vertical change? Answer: -265 feet

Section 1.7 Multiplying or dividing 2 real numbers with same sign: Result is a positive number. Answer is positive if it’s either a positive times a positive or a negative times a negative. Examples:

Examples: Multiplying or dividing 2 real numbers with different signs: Result is a negative number If multiplying more than two numbers together, count the number of negative signs: if it’s odd, the answer is negative, if it’s even, the answer is positive Examples:

Example from homework Multiply. (−7)(2)(−2)(−3) Answer: -84

Example from homework Evaluate. − 3 2 Answer: -9

Some more rules for multiplying and dividing: If b is a real number, 0 · b = b · 0 = 0. Multiplicative inverses or reciprocals are two numbers whose product is 1. Quotient of any real number and 0 is undefined. The quotient of 0 and any nonzero real number = 0.

Example from homework Find the reciprocal or multiplicative inverse. − 8 11 Answer: -11/8

Example from homework If 𝑥=−7 and 𝑦=−4, evaluate the expression. 9−5𝑥 𝑦+4 Answer: N

If a and b are real numbers, and b  0, In other words, never write a final answer with a negative sign on the bottom. Example Simplify the following.

Today’s homework on 1.6 & 1.7 is due at the start of the next class period. Reminder: You should be doing this homework without using a calculator, because calculators can’t be used for Quizzes 1 or 2, Test 1 or the Gateway Quiz.

and begin working on the homework assignment. You may now OPEN your LAPTOPS and begin working on the homework assignment.