3 median line

[panicatthelunchbar]

 with a 3 median line, if we were to find the equation: the gradient can be found by (x lower, y lower) and (x upper, y upper)?
Then the value for c would be substituting a point or using the formula c=1/3 (y's added-m( x's added)) ??

do you guys use another point to find c or the formula....or CAS median-median line feature? OMG -_-

[StumbleBum]

with a 3 median line, if we were to find the equation: the gradient can be found by (x lower, y lower) and (x upper, y upper)?
Then the value for c would be substituting a point or using the formula c=1/3 (y's added-m( x's added)) ??

do you guys use another point to find c or the formula....or CAS median-median line feature? OMG -_-

To find the gradient you would do it as you said. Find the and or and value, then find the and or and . Then apply them to the formulae: , where is the gradient and solve for .

This can also be written as or

For the value, I would use the formulae:
and then you just put in corresponding and values from your graph, along with your newly found value to solve for .

[panicatthelunchbar]

so scrap the c= 1/3 (y's - m (x's))??

[StumbleBum]

so scrap the c= 1/3 (y's - m (x's))??

You can use that if you feel more comfortable doing so. I personally have never seen that formulae through all my years of schooling, so I can't really comment on which may or may not be easier to use.

With that formulae, what do you mean when you say y's and x's..?

[panicatthelunchbar]

y's - all the y coords of the 3 medians added together
x's - all x coords of the 3 medians added together

i think this one just gives u a more accurate answer, whereas using an x and y will be not as accurate....but i think it should be fine!
thanks!

[StumbleBum]

y's - all the y coords of the 3 medians added together
x's - all x coords of the 3 medians added together

i think this one just gives u a more accurate answer, whereas using an x and y will be not as accurate....but i think it should be fine!
thanks!

Well, using VCAA 2006 exam 2 question 3.b as an example they both received the exact same solution for the value of C. I still think y=mx+c is a much quicker way, although either way would be fine in the exam and in the end it's your decision.

[panicatthelunchbar]

awesome, thanks StumbleBum