Question 155243: Find the equation of the line that represents the number of book sales
1,11,500 and 4,13,600
Answer by nerdybill(7384)   (Show Source):
You can put this solution on YOUR website! The problem gives you two points on the line:
(1,11500) and (4,13600)
.
This site describes linear equations quite well:
http://en.wikipedia.org/wiki/Linear_equation
.
The strategy is to put in a "two-point" form:
Given two points:
(h,k) and (p,q), and has slope m = (q−k)/(p−h)
y-k = m(x-h)
.
So, if:
(h,k) and (p,q) were:
(1,11500) and (4,13600)
.
Then, to find the slope:
m = (q−k)/(p−h)
m = (13600−11500)/(4−1)
m = (13600−11500)/(4−1)
m = 2100/3
m = 700
.
Now, we plug it all into:
y-k = m(x-h)
y-11500 = 700(x-1)
y-11500 = 700x-700
y = 700x+10800 (this is what they're looking for)
|
|
|
