Section 5.1.1

Direct and Inverse

Variation

Lesson Objective:

Students will:

• Formally define and apply inverse and direct variation.

1:

6.65 = 1000k

p(120,000) = 0.00665($120,000)

p(120,000) = $798

p(B) = 0.00665B

1:

2:

2:

5-3: Suppose y varies directly with the square of x.

a: Express this relationship generally using k as the constant of variation.

2y kx=

5-3:

b: Solve for the specific solution (find the value of k and use it to write the equation of variation) if y = 3 when x = 2 .

23 3 , so y

4 4k x= =

5-3:

c: Use the equation from part (b) to find y when x = -3.

274

y =

Assignment

Pg 230  #5-4 TO 5-12