If X and Y are different positive integers and 3x+y=17, the difference between the largest possible value of y and the smallest possible value of y is?
i think its infinite but idk for sure, maybe ask someone like... ummmm.... @wio @whpalmer4 or someone im so sorry
do i message him/her?
yeah ig ^_^
um how long will it take for them to reply?
sorry i couldnt be more help... idk... they are online i believe
Oh its, thank for telling me who to ask :)
@torchriswil
yvw ^_^
\[3x+y=17\]Solve for \(y\), what do you get?
y=-3x+17
Okay, can we get y = 1 and still have x be a positive integer?
no
wait actually yes
Really, what value will x have in that case?
wait wait wait noo i mean no
Okay, that's better :-) what's the smallest value we can have for y?
2
Very good. What's the largest value we can have?
Why don't you try finding the value of \(x\) for \(y = 3, 4, 5, \)etc. and see if you see a pattern developing...
its subtracting by 3
Okay. so what is the largest value of y we can have and still have a positive value of x?
might try plotting x,y on a graph...
5
sorry i am stumped i would graph it for you but i dont know what the second equation is
y = 5? are you sure about that?
there's only one equation... \[y = -3x+17\] We want the biggest value of \(y\) that is a positive integer where \(x\) is also a positive integer.
no wait its not 5
Does \[y = -3x+17\]remind you of the equation for a line in slope-intercept form, perhaps?
yes
is it y=14
ding ding ding! we have a winnah! So what is the maximum difference between the smallest possible value of \(y\) and the largest possible value?
12
i know this but since there is no second equation their is no point in it and there is no value for x witch would make the problem super easy but i honestly don't know where to start do you @whpalmer4..
Here's a graph of the line produced by that equation. I have a vertical line at each positive integer value of \(x\) and a horizontal line at each positive integer value of \(y\) that matches with one of those values of \(x\).
It's clear that we can't get a bigger value of \(y\) than 14, or a smaller one than 2, agreed?
mhm
no the graph is infinite so it could go on forever but it would go into negative numbers i see the largest is 14 but the smallest is not 2
correct?
Remember, both \(x\) and \(y\) must be positive integers!
Yea i know
oh then yes you are correct i over looked the fact it was positive this was what confused me im sorry and ys the answer is 12
if we went to x=6, then y = -3(6)-17 = -1, and that's not a positive integer. Glad we're all in agreement. I think this horse, if not dead, is at least going to stay down on the ground until we're all out of sight :-)
whpalmer4 may you help me with another question?
post it and tag me, I need to help another guy who did so while I was working this one with you.
nice idiom
who do i tag you?
just write @whpalmer4 under your question like i just did
oh ok thank you
no problem :)
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