Lesson 5 (Algebraic Expressions) What is an algebraic expression? What is the difference between an expression and an equation? A math phrase that has a combination of variables, cumbers, and operations. An equation has an equal sign, and expression does not. You can solve an equation, you simplify an expression.
Lesson 5 (Algebraic Expressions) Vocabulary in an expression: Example: 5x + 8y - 10 Constant: Quantity that stays the same. A number by itself with no variable. Variable: Quantity that changes, represented by a letter. Coefficient: A number that multiples a variable, the number in front of the variable.
Lesson 5 (Algebraic Expressions) What is a polynomial? Monomial: Has one term. Binomial: Has 2 terms. Trinomial: Has 3 terms. A polynomial is an expression that has addition and subtraction signs separating terms. 8, x 2, 5y, 4a/3 5y+8, 6x-2, 7y 2x 2 + 5x +9 The sign in front of the number determines if it is positive or negative.
Lesson 5 (Algebraic Expressions) Example First, identify variables and label them. Next, decide what operations are used. Joe runs a car washing business. He charges $35 per car. His assistant Shawn can wash 1 more car per hour than Joe can. Write an expression that represents the income they can earn in 6 hours.
Lesson 5 (Algebraic Expressions) Example Jake, Barb, and Felix all have part- time jobs after school. Jake earns $5 more per week than Felix, and Barb earns twice as much per week as Jake. The combined earnings are $115 per week. Write an equation that can be used to find how much each student earns per week.
Lesson 5 (Algebraic Expressions) Example Jessica has been saving quarters and dimes in a jar. Write an expression that represents the amount of money in the jar.
Lesson 5 (Algebraic Expressions) Example The diameter of the larger of 2 circles is 4 cm greater than the diameter of the smaller circle. The smaller circle has a radius of r. Write an expression that represents the difference between the circumferences of the larger and smaller circles.