Lesson 5:5 Solving One-Step & Two-Step Equations · 2019-01-07 · Lesson 5:5 Solving One-Step & Two-Step Equations 2 x = + 4 2 3 2 y = 1 9 n 2 3-x = 12 2 =10 ALGEBRAIC EXPRESSIONS

Lesson 5:5

Solving One-Step & Two-Step Equations

2x = 42 3 + 2y = 19

n2 = 123-x

2 =10

ALGEBRAIC EXPRESSIONS

• Algebraic Expression is a mathematical phrase that can contain ordinary numbers, variables (like x or y) and operators (like add,subtract,multiply, and divide)

Examples

a + 1

ab

b-c

(a+1)2

• Algebraic Equation is a mathematical equation consisting of an expression, an equal sign, and another expression.

• It is similar to the scales to the right and must always remain balanced...one side must always equal the other.

• Examples:

1. 4a = 12 2. 15 + b = 9 3. 6x + 25 = 145

ALGEBRAIC EQUATIONS

Solving Algebraic Equations...

• Your goal is to get the variable by itself on one side of the equation.

• To eliminate a term on one side of the equation, you use the opposite mathematical operation.

• What you do to one side of the equation, you MUST do to the other side of the equation. This keeps the equation balanced!

• Check your answer by substituting the value back into the original equation.

Review Solving 1-Step Equations

You can check out a 2 minute review of 1-step equations on Khan Academy:

https://www.khanacademy.org/math/algebra/one-variable-linear-equations/alg1-one-step-mult-div-equations/v/solving-one-step-equations-2

1. Get the variable by itself2. Use the inverse operation 3. Check your answer by plugging in the value you found for

the variable

How to solve 1-step equations:

4a = 12 n6

= 3x-5=12 y+2=17

Review Solving 1-Step Equations

Let's Practice:

u-6

-9 =

8 = -4 + x

-165 = 15a

-1 = b - 151.

4.3.

2.

Solving 2-Step Equations

• 2 Step Equations require two mathematical operations (+, -, ×, ÷)

Solve them using opposite of PEMDAS... Use SADMEG• Subtract or Add• Divide or Multiply• Exponents

• Grouping (parenthesis, absolute value, fraction bars,etc)

Spend 6 minutes watching this video, called

Solving Two Step Equations: The Basics

https://www.youtube.com/watch?v=9ITsXICV2u0

m + 9 3

a - 4

2-Step Equations

Let's Practice:

3 + u -6-9 =

8 = -4 + 2x

-165 = 15a - 30

-1 = - 15b7

1.

4.3.

2.

3+u is grouped because it's above a fraction bar. Put ( ) around it to help you see it.

Fractions in Equations.....

1. = 10 2. = 3. 2m + = 10

4. x + 2 = 14 5. 3 + a = 13

15

a3

n2

47

23

16

6. -1 = 5 + x 7. m + 9 = 86 3