Symbols Variables and Types of Sentences used in

Symbols, Variables, and Types of Sentences used in Algebra. Equalities = Equals- is the same as Inequalities < > Congruent- same size and shape Similar- same shape Is less than Is greater than Is less than or equal to Approx. equal to = Not equal to

What is a variable? A variable represents an unknown value. 1) 3 + ___ = 10 2) 6 + = 9 3) 8 + x = 12 4) 5 + = 8 These are all variables

Expressions vs. Equations Sentences Expressions Numerical Variable 2+3 5(8) -4 X+7 8 - 3 y Equations 2+3=5 4 + 2(3) = 10 - X 4 = 13 11= 3 + 2 m Inequalities 9 -5>3 6 y -4<8 Open sentences have solutions and can be solved.

Open sentences have solutions and can be solved. Variable Equations - 4+m=7 4 4 - Variable Inequalities - m=3 5 + y < 91 5 5 - y < 86 Solutions

Identify each as an expression, sentence, open sentence, equation, or inequality. 1) 3 x + 5 = 11 Sentence, open sentence, equation 2) 7 < 2(5) + 3 Sentence, inequality 3) 5(3) - 2 Expression 4) 6 m + 2 > 3 Sentence, open sentence, inequality

Multiplication and Division Symbols Ways to Multiply 5 x 7 5 Ways to Divide 8 8 4 7 5(7) 5 7 4 8/4 With variables. . . 5 x 5 x 5 axy 4 8

Squares vs. Square Roots

Solve the following: One Solution or Two Solutions

Follow the pattern! True if x is positive. Not true if x is negative.

Follow the pattern! True Always!

Solved a different way: One Solution or Two Solutions