## anonymous one year ago Which equation represents a linear function? Equation 1: y = 2x2 + 1 Equation 2: y2 = 8x + 1 Equation 3: y = 5x3 – 1 Equation 4: y = 7x – 1 Equation 1 Equation 2 Equation 3 Equation 4

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1. anonymous

the numbers after the variables are exponents

2. anonymous

linear functions don't have exponents. Which is that?

3. anonymous

equation 4

4. anonymous

i have more questions

5. anonymous

Brian and Cyril spend a certain amount of money from their money box each month to buy plants. The table shows the relationship between the amount of money (y) remaining in Brian's money box and the number of months (x): Function 1: Number of Months (x) Amount Remaining (dollars) (y) 1 65 2 59 3 53 4 47 The equation shows the relationship between the amount of money, y, remaining in Cyril's money box and the number of months, x. Function 2: y = –8x + 65 Which statement explains which function shows a greater rate of change? Function 2 shows a greater rate of change, because Cyril spends $8 each month and Brian spends$6 each month. Function 2 shows a greater rate of change, because Cyril spends $65 each month and Brian spends$18 each month. Function 1 shows a greater rate of change, because Brian spends $18 each month and Cyril spends$57 each month. Function 1 shows a greater rate of change, because Brian spends $6 each month and Cyril spends –$8 each month.

6. anonymous

@peachpi

7. anonymous

use the slope formula to find the rate of change for function 1 $m=\frac{ y_2-y_1 }{ x_2-x_1}$ Pick any two points to plug in

8. anonymous

1 and 65

9. anonymous

you can use 1 for x_1 and 65 for y_1. Now pick another point for x_2 and y_2.

10. anonymous

Then plug them into the formula

11. anonymous

i dont understand

12. anonymous

@perl

13. anonymous

Each pair of numbers in that table represent a point on a line. They're asking you to find the slope of the line that has the points (1, 65), (2, 59), (3, 53), and (4, 47). Does that make sense?

14. anonymous

yes

15. anonymous

function 2 has a rate of change of 8, am i right?

16. anonymous

-8

17. anonymous

but the change is by 8, negative or not

18. anonymous

Do you understand how to get the rate of change for function 1?

19. anonymous

no

20. anonymous

not really. the direction matters. ROC of 8 means the function is increasing. ROC of -8 means it's decreasing

21. anonymous

btw these are the answer choices: A: Function 2 shows a greater rate of change, because Cyril spends $8 each month and Brian spends$6 each month. B: Function 2 shows a greater rate of change, because Cyril spends $65 each month and Brian spends$18 each month. C: Function 1 shows a greater rate of change, because Brian spends $18 each month and Cyril spends$57 each month. D: Function 1 shows a greater rate of change, because Brian spends $6 each month and Cyril spends –$8 each month.

22. anonymous

For function 1 let's just consider the 2 points (1, 65) and (2, 59). This is how you put them into the slope equation |dw:1435794971386:dw|

23. anonymous

i no the slope equation is y=mx+b

24. anonymous

by slope equation, I meant the equation you use to find the slope of a line. y = mx + b is the slope-intercept form of a linear function. It uses the slope, but sometimes, like in function 1, you don't have an equation in that format. So you have to find the slope using points and the equation above.

25. anonymous

and i no that the answer is either A or D

26. anonymous

can u tell me if its either A or D cause i gotta go soon

27. anonymous

RE: D. Does spending -\$8 a month make sense?

28. anonymous

i guess not

29. anonymous

so its A?

30. anonymous

yes

31. anonymous

Thank you so much

32. anonymous

np

33. anonymous

well i gotto go so bye