1a. Write the expression 3n – 4n – 8 as a sum. How does this help you identify the terms of the expression? Identify the terms. 3m + (-4n) + (-8) Writing an expression as a sum clarifies the parts being added and their signs. 3m, -4n, -8
1b. Explain and illustrate the difference between a term and a coefficient. A term is a part of an expression being added. A coefficient is a numerical factor of a term. Ex. 4x is a term of 4x + 1. Its coefficient is 4.
1c. What is the coefficient of x in the expression x - 2? Explain your reasoning. 1 x = 1∙x so the numerical factor of the term is 1.
1d. What is the value of 1-18+25 if you subtract then add? If you add then subtract? Why is the order of operations necessary? Subtract and then add 8 Add then subtract -42 Results will vary if a consistent order is NOT followed.
VOCABULARY evaluate An algebraic expression – substitute the value(s) of the variable(s) into the expression and simplify using the order of operations
REFLECT - Part 2 2a. Explain why x and 4x - 10 are factors of the expression x(4x - 10)3 rather than terms of the expressions. What are the terms of the factors 4x – 10. The expressions x and 4x – 10 are multiplied, not added, to form x(4x-10)3, which makes them factors, not terms 4x, -10
2b. Evaluate 5a + 3b and (5 + a)(3 + b) for a = 2 and b = 4. How is the order of the steps different for the two expressions? 5a + 3b 22 Multiply first then add (5 + a)(3 + b) 49 Add first then multiply
2c. In what order would you perform the operations to correctly evaluate the expression 2 + (3 – 4)∙9? What is the result. Subtract, then multiply, then add -7
2d. Show how to move the parentheses in the expression 2 + (3 – 4)∙9 so that the value of the expression is 9. ( 2 + 3 – 4) ∙ 9