Students will make Connections to Algebra

 Variable:  A letter used to represent a range of numbers

 Values:  The numbers (constants)

 Variable expression:  Variables, constants, and your operations

 Numerical expression:  Constants and operations (just numbers)

 Evaluate:  Simplify: Distribute Combine Like Terms PEMDAS

Variable ExpressionsMeaningOperation 3x, 3 * x, (3)(x) times 14, 14 y y divided by 9 + a plus 12 – b minus In this algebra class, we use parentheses “(3)(2)” or number and variable “3x” to demonstrate multiplication so that there is no confusion with decimal points or anything else!

 Evaluate the variable expression when x = 5 Solution ExpressionSubstituteSimplify 5x5x= 5( )= 40 x =40= 5

1. 10x2.20 x x4. X + 8

Find the distance d traveled in 30 minutes by a remote control car going an average speed of 10 miles per hour. Use the formula: distance equals rate r multiplied by time t. Solution d = rtWrite formula = ( )( )Substitute for r and t. = = Simplify Answer The distance traveled by the remote control car was miles

5. Using a variable expression, find the distance traveled in 20 minutes by a remote control car moving at an average speed of 9 miles per hour. d = rtWrite formula = ( )( )Substitute for r and t. = Simplify Answer The distance traveled by the remote control car was miles

The perimeter P of a triangle is equal to the sum of the lengths of its sides: Solution 1. Write the formulaP = a + b + c 2. Substitute 6 for a, = for b, and 13 for c. 3. Simplify the formula = Answer The triangle has a perimeter of meters. c = 13 m b = 11m a = 6m P = a + b + c Find the perimeter of the triangle in meters

6. Find the perimeter of a triangle with sides 7 centimeters, 12 centimeters, and 17 centimeters long. P = a + b + c = + + = The triangle has a perimeter of centimeters