lesson 5:5 solving one-step & two-step equations · 2019-01-07 · lesson 5:5 solving one-step...
TRANSCRIPT
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