1. Using Formulas Lesson 3-4

2. Math Vocabulary Formula: A math statement, usually an equation, that is represented by variables and is used to solve for a specific answer

3. Working with Formulas To work with a formula requires  substitution

4. Formulas Formula: d = r t distance = rate x time To find d, r, or t  use substitution: d = 12 mi, t = 4 h 12 = r 4  12 = 4 r

5. Formulas Formula: F = n + 37 4 Fahrenheit (temp) = # of chirps + 37 4 To find F  use substitution: n = 100 chirps F = 100 + 37 4

6. Formulas Formula: P = 2 l + 2 w Perimeter = (2 x length) + (2 x width) To find P  use substitution: l = 10 w = 15 P = 2(10) + 2(15)

7. Formulas Formula: Fº = 1.8 Cº + 32 Fahrenheit = (1.8 x Celsius) + 32 To find F  use substitution: Cº = 6 Fº = 1.8 (6) + 32

8. Practice… a) Use d = r t r = 9 m/hr, t = 12 h Find d b) Use F = n + 37 n = 144 Find F 4 c) Use P = 2 l + 2 w Find P d) Use F º = 1.8 C º + 32 C = 8 Find F