1. Warm Up – August 14, 2017 Solve for y. 3 + y = 2x 6x = 3y
Write and equation that describes the relationship. 3.
Solve for x.
= 𝑥 15
= 1.5 𝑥 X 1 2 3 4 Y 6 9 12

2. During: 2‐2 Direct Variation Learning Target: I can interpret direct variation equations. Key Terms: direct variation, constant of variation

3. Key Terms: direct variation – formula for the function is y = kx, where k cannot equal 0, x represents input values, and y represents outcome values. constant of variation – the ratio of all output‐input pairs equals the constant k.

4. “I do” Identifying Direct Variation From TablesX Y 1 2 3 6 4 8 X Y 1 4 2 8 3 11

5. “You do”
a. b. X Y 3
-21 2
-14 1 -7 X Y 2 5 3 7 6 13

6. “I do” Identifying Direct Variation From Equations
a. 3y = 7x b. 7y = 14x + 7

7. “You do”
a. 5x + 3y = 0 b. y = 𝑥 9

8. “I do” Using Proportions to Solve a Direct Variation
Suppose y varies directly with x, and y = 9 when x = What is y when x = 21?

9. “You do”
Suppose y varies directly with x, and y = 15 when x = 3. What is y when x = 13?

10. “I do” Graphing Direct Variation Equations
a. y = ¾ x

11. “You do”
y = -2x

12. Homework
Pg. 71 # 8, 10, 14, 15, 17, 22, 27, 44