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Author Topic: HH  (Read 1680 times)

blotz

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HH
« on: May 02, 2013, 06:25:02 PM »
yeah i know theres a nother topic but i'm to lazy
anyways


Caleb drew a scatter plot for the average number of hours of homework y he received each year in school x. A line of best fit passed through the points (5, 1.5) and (8, 3.75). Predict the number of hours of homework that Caleb can expect to receive in 12th grade.

A. 4.75
B. 5.25
C. 6.75
D. 7.25



i got like
1.75

used point slope intercept form and then substituted it with and got the y-intercept with y intercept form and then calculated it, but got y=3/4*12-3.75
and yeah...

HELP PLEASE

tuto99

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Re: HH
« Reply #1 on: May 02, 2013, 06:35:07 PM »
You can use slope formula to figure out y for 12 grade, or if you have the graph you can make a guess by making an imaginary line to the point you are trying to figure out.

Formula for slope:

y2 - y1 / x2 - x1
 
Or Rise/Run

blotz

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Re: HH
« Reply #2 on: May 02, 2013, 06:37:58 PM »
i did!!
but it didn't work

tuto99

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Re: HH
« Reply #3 on: May 02, 2013, 06:39:14 PM »
Could you give me the graph you are using?

blotz

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Re: HH
« Reply #4 on: May 02, 2013, 07:13:26 PM »
no graph bro

tuto99

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Re: HH
« Reply #5 on: May 02, 2013, 07:32:05 PM »
The answer is C. It's not hard man.
Here are the steps I did to solve this problem.
1. Find the slope, which is .75

2. apply the first (or second) ordered pairs and slope into y-intercept form and solve

1.5 = .75(5) + b, so b = -2.25

3.apply everything in y-intercept form to solve the problem

y = .75(12) - 2.25, so y = 6.75