Determine the x-coordinate that would yield a y-coordinate of 30, assuming the pair follows the same trend that currently exists in the data set below.

{(45, 18), (38, 21), (26, 31), (64, 13), (29, 28), (33, 25), (49, 17)}

A.

18

B.

27

C.

36

D.

38

Question

Determine the x-coordinate that would yield a y-coordinate of 30, assuming the pair follows the same trend that currently exists in the data set below.


{(45, 18), (38, 21), (26, 31), (64, 13), (29, 28), (33, 25), (49, 17)}


A.
 
18
 

B.
 
27
 

C.
 
36
 

D.
 
38

anonymous · Answer

fit y = m x + b, then substitute y=30 to find that x.

anonymous · Answer

I am not good with Algebra, I am struggling with slope as well so that doesn't help,

anonymous · Answer

Look at the two points (26,31) and (29,28). Notice as our x values increase our y values decrease from 31 to 28. Assuming we have a continuous function here we can determine that the x value for which y=30 must lie between x=26 and x=29. That leaves only answer choice b.

anonymous · Answer

use the 5th and 6th ordered pairs to find the slope

anonymous · Answer

any two pairs will do, but getting two close to your target helps

anonymous · Answer

well, you see (26, 31) which is close to your (x, 30) and you know that y is decreasing generally as x is increasing, so y is increasing as x decreases, so y should be just a bit larger than 26.

anonymous · Answer

Thank you all! I really needed help, I'm terrible with Algebra...

anonymous · Answer

I meant x should be just a bit larger than 26....