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lilwendy722
May 1, 2008, 04:01 PM
:confused: today I had math class with my teacher mr.siu, but I'm confused about one algebraic equation. He asked me what the variables stand for and what are the answer(s) to this question: y=mx+b

:p ;) :confused:

I already understand that m is the slope of the line and b is the y-intercept, however I need to know what y and x is supposed to mean and stand for... try to answer me with an understandable answer with steps... the h.w. s due tomorrow and I really need the help! Thanks lots! :D

if u can try to reply to me as soon as u can, would you! Thanks once again and bye bye!! :D

KISS
May 1, 2008, 04:26 PM
y is the dependent variable. It's value depends on x.

x is the independent variable. It's value is arbitrarily chosen.

You can also describe it as the equation of a straight line having a slope (delta y/delta x) and intersects the y axis at (0,b).

nanci92
May 1, 2008, 04:49 PM
HI! I just learned that and I am in Advanced Math so I am pretty sure I know this.

Y=MX+B
this formula is called slope intercept form

You are right about the b standing for the y intercept and m standing for the slope.

The easiest way to explain this would be y and x are coordinates on a coordinate plane. You following me?

if you substitute values in for x you get the answer to y. Which would create an ordered pair.

Here's an example.
y=2x+1

The 1 is the y intercept. (the place where it crosses the y axis)

The 2 is the slope.

You know that an ordered pair is (x,y) right?

so lets just substitute numbers in the problem.

for x we can substitute 1

y=2(1)+1

so that simplified would be y=2+1 (becuase you multiply the x by the slope)

so the number that we substituted in is 1 right.

so the ordered pair would be (1,3)

If this doesn't make it easier to understand you can go to:

Purplemath (http://www.purplemath.com)

and in the search box, type in slope intercept form
that will help you loads.

Please rate my answer.
THANKS!