Quote:
Originally Posted by kimsoohanmoo
Find the relation ship between the set of ordered pairs
(-3, 7), (-1, 3), (3, -5), (4,-7)
please help me with this Ive been stuck on this for a very, very long time.
Im not looking to graph them I mean like (example)
(4, 2), ...etc
the relationship between them is that y is the square root of x.
I know for the question I asked it isnt multiplication or division or the square root so it must be some sort of equation right. Ive been working on this for two days.............  |
If you graph them you can see these coordinates form a line.
To check that it is a linear function look to see that there is a constant rate of change (slope) between the points.
(-3, 7), (-1, 3): m = (3 - 7) / (-1 - -3) = -4 / 2 = -2
(-1, 3), (3, -5): m = (-5 - 3) / (3 - -1) = -8 / 4 = -2
(3, -5), (4, -7): m = (-7 - -5) / (4 - 3) = -2 / 1 = -2
So yes, there is a constant rate of change between the points.
To find the equation try using point-slope form of a line.
First pick a point, say (4, -7). Point-slope form is y - y1 = m(x - x1).
Then y - -7 = -2(x - 4)
y + 7 = -2x + 8
y = -2x + 1
Hope this helps.