2 Remember:1. A variable is a letter used to represent an unknown value.2. A numerical expression includes numbers and operations.3. An algebraic expression contains variables, numbers and operations.
3 x a b y Variables are letters that represent unknown values. How did I What do I represent?How did Iget here?What am I?xaI am so unknownbyVariables are letters that represent unknown values.
4 Numerical Expressions Numerical expressions include numbers and operation symbols.
5 n Algebraic Expressions An algebraic expression includes: Numbers Operationsand Variablesn
6 Let’s look at examples of a numerical expressions: 3287(4)
7 Let’s look at examples of algebraic expressions. 2
8 Algebraic expressions like phrases in English are incomplete. EquationsAlgebraic expressions like phrases in English are incomplete.An equation, like a sentence, is complete. You will notice theinclusion of a very special symbol.An equation is made up of numbers, variables,and an equal sign.3b + 5 = 26
9 Rewrite these verbal expressions as algebraic expressions. 1. the sum of s and 12s+122. the product of 15 and some number15n3. n to the seventh powern74. 56 increased by twice a number56+2a5. Four less than a numbern-4
10 Let’s write equations for these sentences. 1. Forty-three less than n is equal to 35.n – 43 = 352. Seven more than y is 13.y + 7 = 13