1. GRAPHS IN ECONOMICS

2. STUDY GUIDE MULTIPLE CHOICE, #4-19 SHORT ANSWER, #2-8

3. A POSITIVE RELATIONSHIP X Y 0 5 110 215 320 425 530 635 740 845 950

4. A NEGATIVE RELATIONSHIP X Y 0 20 118 216 314 412 510 68 76 84 92 100

5. SLOPE CHANGE IN Y GIVEN A CHANGE IN X How much one variable changes when another variable changes. How much more people wish to sell as the price rises. How much current consumption must fall to increase capital production

6. SLOPE ON A STRAIGHT LINE RISE OVER RUN CHANGE IN Y: Y 2 -Y 1 DIVIDED BY CHANGE IN X X 2 -X 1

7. POSITIVE RELATIONSHIP STRAIGHT LINE X Y 110 215 320 425 530 635 740 845 950 1055 Y 2 -Y 1 15-10 = 5 X 2 -X 1 2-1 = 1 5/1=5 THE SLOPE IS +5

8. NEGATIVE RELATIONSHIP STRAIGHT LINE X Y 0 20 118 216 314 412 510 68 76 84 92 100 Y 2 -Y 1 12-14 = -2 X 2 -X 1 4-3 = 1 -2/1 = -2 THE SLOPE IS -2

9. SLOPE ON A CURVE X Y 016 111 28 37 48 511 616 723 832 943 1056

10. SLOPE ON A CURVE First the curve has a negative slope, it reaches a minimum and then it has a positive slope. At the minimum the slope is zero.

11. SLOPE ACROSS AN ARC CREATE A STRAIGHT LINE BETWEEN THE TWO POINTS OF THE ARC CALCULATE SLOPE JUST AS FOR A STRAIGHT LINE

12. SLOPE ACROSS AN ARC Pt. 1 (20,8) Pt. 2 (60,16) Y 2 -Y 1 16-8 = 8 X 2 -X 1 60-20 = 40 8/40 =.2 THE SLOPE IS.2

13. SLOPE ACROSS AN ARC Pt. 2 (16, 0) Pt. 1 (7, 30) Y 2 -Y 1 16-7 = 9 X 2 -X 1 0-30 = -30 9/-30 = THE SLOPE IS -.3

14. SLOPE AT A POINT ON A CURVE Draw a tangent to the curve Calculate the slope along the tangent Note that the slope should be comparable to the slope along an arc.

15. SLOPE AT A POINT ON A CURVE Pt. 2 (0, 10) Pt. 1 (40, 4) Y 2 -Y 1 10-4 = 6 X 2 -X 1 0-40 = -40 6/-40 = THE SLOPE IS -.15

16. SLOPE AT A POINT ON A CURVE Pt. 2 (3, 3) Pt. 1 (8, 23) Y 2 -Y 1 3-23 = -20 X 2 -X 1 3-8 = -5 -20 / -5 = THE SLOPE IS 4