1. Survey of Math Seminar, Unit 4 Tonight: Variation, Inequalities, and Coordinate Geometry Math Quote of the Week: “The science of pure mathematics... may claim to be the most original creation of the human spirit.” –Alfred North Whitehead

2. Direct Variation #26. r varies directly as the square of s. Determine r when s = 2 and k = 13 Henry’s law: P = HC P is partial pressure, H is Henry’s constant, C is concentration of pollutant gas

3. Inverse Variation Suppose H varies inversely to G. If G is 12 and k is 4…

4. Joint Variation Area of Triangle is A = ½ bh What is area if b and h are 4 and 6 respectively?

5. Combined Variation Darcy’s Law: Q = KAP/L Q is flow, K is constant, A is area, L is length, and P is hydrostatic pressure difference

6. The Coordinate Grid Quadrant 2 Quadrant 1 Quadrant 3 Quadrant 4

7. Graphing Linear Equations Graph y = 2x – 3 x y pair

8. Graphing Linear Equations Graph 4y + 6x = 12 x y pair

9. Slope Slope = m = y 2 – y 1 x 2 – x 1 using points (x 1,y 1 ) and (x 2,y 2 ) (-2,-4) and (3,7) slope, m =

10. Slope #70 … our points are (-5, 6) and (8, 8) Slope = m = y 2 – y 1 x 2 – x 1

11. Inequalities –9t + 6 > 16

12. Inequalities –9(h – 3) + 2h < 8(4 – h) –9h +27 + 2h < 32 – 8h