1. Homework Review

2. Literal Equations and Modelling

3. Solving Equations and Formulas
Objectives:
Solve literal equations (formulas, with letters) for a specified variable
Apply these skills to solve practical problems

4. Definitions:
An equation is a mathematical sentence that contains an equal sign ( = ).
Ex: y = 3x
A formula is an equation that states a rule for the relationship between certain quantities.
Ex: A = lw What do A, l, and w stand for?

5. Solving an Equation 1) Solve the equation 3x + 4 = 13 for x.
Ask yourself:
What is the first thing being done to x,
the variable being solved for?
x is being multiplied by 3.
What is being done next?
4 is being added to 3x.

6. Solving a Formula

7. Solving a Formula 1) Solve the equation wx + y = z for x.
Ask yourself:
What is the first thing being done to x,
the variable being solved for?
x is being multiplied by w.
What is being done next?
y is being added to wx.

8. Solving an Equation

9. Show all of your work!
YOUR TURN!!!
Ex: -5x + y = -56

10. Show all of your work!
First, subtract y from both sides of the equation.
Next, divide by -5.
This process actually requires LESS WORK than solving equations in one variable 
Ex: -5x + y = -56
- y -y
-5x = y
x = y = 56 + y

11. Let’s try another: Ex: Solve 2x - 4y = 7 for x. +4y + 4y 2x = 7 + 4y
x = 7 + 4y 2
This fraction cannot be simplified unless both terms in the numerator are divisible by 2.

12. Another example: Solve a(y + 1) = b for y. a a y + 1 = b a - 1 -1
Why not ?

13. Try a few on your own. Solve P = 1.2W for W. H2
2. Solve P = 2l + 2w for l.
3. Solve F = 9C + 32 for C. 5

14. The answers: 1. 2. 3.

15. Literal Equations Worksheet
Classwork/Homework
Literal Equations Worksheet