Unit 1: Day 3 – 1 and 2 step equations

Warm-up Write an equation to model the situation. The total cost of n cartons of milk is $3.60. Each carton costs $0.45. Simplify: 2. 6t + 2 – 4t + 5 3. Evaluate: 2x - y for x = 4 and y = - 3

HW 1.3 check

The total cost of n cartons of milk is $3.60. Each carton costs $0.45. Our equation was: 3.60 = 0.45n How do we find out how many cartons of milk were bought?

“Whatever you do to one side you must do to the other!” Solving Equations! “Whatever you do to one side you must do to the other!”

Equal What does it mean for two things to be equal?

Are these equal? =

Equalities Equations are statements where two values are EQUAL! 4 + 5 = 9

Vocabulary Equivalent Equations are equations that have the same solution or (solutions) A solution of the equation is a value (s) that make an equation TRUE Have students recall what an equivalent expression is.

Are the Equations True? 6 + 10 = 8 + 1 + 5 2(8) + 1 = 8 + 2 + 7 2 + x = 1 + x + 1

Solving Equations (finding equivalent equations) Use INVERSE OPERTATIONS : operations that undo each other EX 1. 8 + x = 5

Inverse Operations: Operation: Inverse: Addition Subtraction (+) (-) Subtraction Addition (-) (+) Multiplication Division (•) (÷) Division Multiplication (÷) (•)

Create an equivalent Equation: N – 3 = 5 2. d + 5 = 7 3. 4 + x = 8 4. -2 + x = 10

Solve 5) 5x = 25 6) 30 = 2v 7) 8)

9. 10.

Solving 2-step Equations How would I solve: 2y – 3 = 7

Solving for a Variable **Order of Operations is REVERSED** 1. Addition and Subtraction 2. Multiplication and Division 3. Exponents 4. Parenthesis

1. 2.

3. 4.

5. 6.

7. 8.

9. 10. What is the ERROR?

Homework 1.3