Problem 1633. Find the right x in a 1. order Polynomal (y = m*x+c)

Created by Martin

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<div style = "text-align: start; line-height: 20px; min-height: 0px; white-space: normal; color: rgb(0, 0, 0); font-family: Menlo, Monaco, Consolas, monospace; font-style: normal; font-size: 14px; font-weight: normal; text-decoration: none; white-space: normal; "><div style="display: block; min-width: 0px; padding-top: 0px; transform-origin: 332px 102px; vertical-align: baseline; perspective-origin: 332px 102px; "><div style="font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-bottom: 9px; margin-left: 4px; margin-right: 10px; margin-top: 2px; text-align: left; transform-origin: 309px 21px; white-space: pre-wrap; perspective-origin: 309px 21px; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="display: inline; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; transform-origin: 0px 0px; perspective-origin: 0px 0px; "><span style="">Given two points in a Cartesian coordinate system, find the x-value on the line y = m*x+b where the y-value is equal to a given value c.</span></span></div><div style="font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-bottom: 9px; margin-left: 4px; margin-right: 10px; margin-top: 2px; text-align: left; transform-origin: 309px 21px; white-space: pre-wrap; perspective-origin: 309px 21px; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="display: inline; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; transform-origin: 0px 0px; perspective-origin: 0px 0px; "><span style="">e.g.: we have the points P1(1,2) and P2(3,6) and we want wo know at which x-value y is equal to c = 8; The input is: x = [1 3], y = [2,6], c = 8.</span></span></div><div style="font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-bottom: 9px; margin-left: 4px; margin-right: 10px; margin-top: 2px; text-align: left; transform-origin: 309px 10.5px; white-space: pre-wrap; perspective-origin: 309px 10.5px; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="display: inline; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; transform-origin: 0px 0px; perspective-origin: 0px 0px; "><span style="">The answer is 4.</span></span></div><div style="font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-bottom: 9px; margin-left: 4px; margin-right: 10px; margin-top: 2px; text-align: left; transform-origin: 309px 21px; white-space: pre-wrap; perspective-origin: 309px 21px; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="display: inline; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; transform-origin: 0px 0px; perspective-origin: 0px 0px; "><span style="">Consider the possibility that there isn't any solution (return NaN) of that there is an infinity amount of points (return Inf). Additionally consider that the point could represent a vertial line.</span></span></div><div style="font-family: Helvetica, Arial, sans-serif; line-height: 21px; margin-bottom: 9px; margin-left: 4px; margin-right: 10px; margin-top: 2px; text-align: left; transform-origin: 309px 10.5px; white-space: pre-wrap; perspective-origin: 309px 10.5px; margin-left: 4px; margin-top: 2px; margin-bottom: 9px; margin-right: 10px; "><span style="display: inline; margin-bottom: 0px; margin-left: 0px; margin-right: 0px; margin-top: 0px; transform-origin: 0px 0px; perspective-origin: 0px 0px; "><span style="">Good Luck!</span></span></div></div></div>

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Solution Stats

88 Solutions
28 Solvers

Last Solution submitted on Oct 28, 2022

Last 200 Solutions

Problem Comments

5 Comments

5 Comments

Show 2 older comments

Dan on 10 Jun 2013

I don't understand the meaning of the problem. If y=c then x=0. Enlighten me, please.

Carlos Adrian Vargas Aguilera on 30 Jun 2013

If y=mx+b, when y=c, x=?

Martin on 23 Jul 2013

Hi everyone:
Dan: in my mathematical understanding (correct me if I am wrong): if y=c the slope m of the curve is 0. but for all x the condition y = c is correct, so x should be infinite
Or is there some error in the solution?

Rafael S.T. Vieira on 4 Oct 2020

The problem description needs to be improved, maybe to something like: Given two points in a Cartesian coordinate system, find the x-value on the line y = a*x+b in which the y-value is equal to a given value c.

goc3 on 8 Oct 2020

The description has been updated.

Solution Comments

Solution 1539536

1 Comment

1 Comment

bainhome on 25 May 2018

Nice one. hard to figure this out.

Solution 270030

1 Comment

1 Comment

Carlos Adrian Vargas Aguilera on 30 Jun 2013

I don't like my solution. I rader prefer David's. JEJE

Solution 258345

1 Comment

1 Comment

Martin on 9 Jun 2013

nice solution :-)

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