## flutterflies Group Title PLEASE HELP! At a corner gas station, the revenue R varies directly with the number g of gallons of gasoline sold. If the revenue is \$24.25 when the number of gallons sold is 5, find a linear equation that relates revenue R to the number of g of gallons of gasoline. then find the revenue R when the number of gallons of gasoline sold is 13.5. one year ago one year ago

1. mjr632 Group Title

Hello, do you understand how to find the equation of a line?

2. mjr632 Group Title

y=mx+b

3. flutterflies Group Title

so how will the variables fit into the equation?

4. mjr632 Group Title

Okay, we need two points to find the slope of the linear equation

5. mjr632 Group Title

Our first point shall be (5, 24.25)

6. mjr632 Group Title

Can you think of another point that we can intuitively know given the question?

7. flutterflies Group Title

(x, 13.5) doesn't give the x value

8. mjr632 Group Title

Okay, we know how much revenue the company makes when they sell 0 gas, correct?

9. flutterflies Group Title

sure.

10. mjr632 Group Title

How much revenue will they make when they sell 0 gas?

11. flutterflies Group Title

wouldn't it just be 0

12. mjr632 Group Title

Correct

13. mjr632 Group Title

the equation for the slope of a line is $m=\frac{y_1-y_2}{x_1-x_2}$

14. mjr632 Group Title

We now have two points (0,0) and (5, 24.25)

15. mjr632 Group Title

Do you see how if we plug in these two points, we can obtain the slope m?

16. flutterflies Group Title

slope would be 4.85

17. mjr632 Group Title

correct

18. mjr632 Group Title

We know that the equation for a line is y = mx + b

19. mjr632 Group Title

and we have the value of m

20. mjr632 Group Title

we also have the value for y and x

21. mjr632 Group Title

which are (5, 24.25)

22. mjr632 Group Title

If we plug in these values, m, x and y, then all we have to find is b

23. flutterflies Group Title

would the equation be y= 4.85x+48.5?

24. mjr632 Group Title

no

25. mjr632 Group Title

24.25 = (4.85)(5)+b

26. mjr632 Group Title

24.25 = 24.25+b

27. mjr632 Group Title

Do you see what b must equal?

28. flutterflies Group Title

b=0

29. mjr632 Group Title

Correct

30. mjr632 Group Title

We now have the full equation

31. flutterflies Group Title

equation will be y=4.85x+0

32. mjr632 Group Title

You got it

33. mjr632 Group Title

Now you just need to find y = 4.85(13.5)

34. flutterflies Group Title

wouldn't the 13.5 be in place of y and not x since the point is (x, 13.5)

35. mjr632 Group Title

no, the amount of gas is your x variable

36. mjr632 Group Title

the profit is your y value

37. flutterflies Group Title

so the answer would be 65.47

38. mjr632 Group Title

Correct

39. flutterflies Group Title

Thank you!!!!

40. mjr632 Group Title

You're welcome, good work!

41. mjr632 Group Title

Did you need any help with any other questions?