SOLUTION: My daughter's algebra book (Glencoe's Algebra 1 page 242) provides one example of this that is totally unlike this problem. Sets of numbered pairs are listed and they are shown pl

Algebra ->  Graphs -> SOLUTION: My daughter's algebra book (Glencoe's Algebra 1 page 242) provides one example of this that is totally unlike this problem. Sets of numbered pairs are listed and they are shown pl      Log On


   

Question 373412: My daughter's algebra book (Glencoe's Algebra 1 page 242) provides one example of this that is totally unlike this problem. Sets of numbered pairs are listed and they are shown plotted as a line on a graph. She is asked to write an equation in function notation for the relation graphed - in this case (4,0),
(2,3)and (0,6). What are the steps to solve this problem?
Thanks very much!
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
write an equation in function notation for the relation graphed -
in this case (4,0), (2,3)and (0,6). What are the steps to solve this problem?
:
Use two pair of coordinates to find the slope (m) which is: m = %28y2-y1%29%2F%28x2-x1%29
:
we will use the 1st and last pair, assign as follows:
x1=4; y1=0
x2=0; y2=6
:
m = %286-0%29%2F%280-4%29 = 6%2F%28-4%29 = -3%2F2 is the slope
:
Use the point/slope formula to find the equation: y - y1 = m(x- x1)
y - 0 = -3%2F2(x - 4)
y = -3%2F2x - -3%2F2(4)
y = -3%2F2x + 6 is the solution for this line
:
We can check this using the 2nd pair of coordinates, replace x with 2, find y
y = -3%2F2(2) + 6
y = -3 + 6
y = +3 which is correct
:
:
Graphically
+graph%28+300%2C+200%2C+-4%2C+5%2C+-8%2C+8%2C+-1.5x%2B6%29+