## 1honey 4 years ago 3. The linear equation represents an estimate of the average cost of gas for year x starting in 1997 (“Consumer price index,” 2006). The year 1997 would be represented by x = 1, for example, because it is the first year in the study. Similarly, 2005 would be year 9, or x = 9. a. What year would be represented by x = 4? b. What x-value represents the year 2018? c. What is the slope, or rate of change, of this equation? d. What is the y-intercept? e. What does the y-intercept represent? f. Assuming this growth trend continues, what will the price of gasoline be in the year 2018? How did

1. 1honey

a. is 2000

2. myininaya

how did you get that without an equation? I would just say these questions cannot be answered since there was not enough information given.

3. 1honey

im sorry the equation is y=0.5x+0.79

4. myininaya

so for the first one you plug in x=4 correct?

5. 1honey

after that im lost

6. myininaya

oh since x=4, then the year is 2000 ok gj now for b....

7. myininaya

so x=1 we have 1997 x=2 we have 1998 x=3 we have 1999 x=4 we have 2000 and so on.. so the equation for the year would be Z=1996+x lets see for x=1, we get Z=1996+1=1997 for x=2 we get Z=1996+2=1998 and so on... so the question is what is x if Z=2018 so we have 2018=1996+x solve this equation for x

8. myininaya

what did you get when you solved the equation that i just typed for x?

9. 1honey

x=22

10. myininaya

ok cool so did you understand everything for b?

11. 1honey

no not really by u breaking it down help me find the answer

12. myininaya

I just made up a variable for the year

13. 1honey

can we do the next one c

14. myininaya

k it wants to know the slope of the line? what is the slope of any line in this form y=mx+b?

15. 1honey

m=

16. 1honey

is that correct

17. myininaya

yes

18. myininaya

so y=.5x+79 has slope_________?

19. myininaya

what is m?

20. 1honey

ok 1 min

21. myininaya

slope=m=.5

22. myininaya

ok

23. 1honey

oh ok the slope is .5 and would b=79

24. 1honey

or the answer to the ? is just .5

25. myininaya

the question c is just looking for slope so it would be .5 the question d is just looking for the y intercept so it would be .79 (I forgot the decimal when I typed it a sec ago)

26. 1honey

therefore the y-intersect would b =0

27. myininaya

the y-intercept is when x=0

28. 1honey

than im lost on problem e

29. myininaya

ok we will come back to it then lets look at the last one average gas is y=.5x+.79 and since we are looking at yr 2018 then x=22 so the average gas for yr 2018 is y=.5(22)+.79

30. 1honey

y=11.79

31. myininaya

ok back to e. the y-intercept is when x=0 because if we were to graph a point on the y axis x would always be zero since we aren't going left and right any from the origin. for example graph (0,5) and (0,-6). where are these points?

32. 1honey

would it be -11