SOLUTION: find the equation of the line that contains the points (2,2)and(-4,5).

Algebra ->  Linear-equations -> SOLUTION: find the equation of the line that contains the points (2,2)and(-4,5).      Log On


   



Question 263: find the equation of the line that contains the points (2,2)and(-4,5).
Answer by terrtwo(10) About Me  (Show Source):
You can put this solution on YOUR website!
The general equation of a line is y = mx + b. To define a specific line, two things are needed: the slope (m) and the y-intercept (b). From the information given, two points, we are able to determine the slope:
m = (the change in y)/ (change in x)
--> m+=+%282-5%29%2F%282+-+%28-4%29%29
--> m = -3/6 = -1/2
Then if we use either of the points (let's use the first one listed above, (2,2)) and the slope in the general equation:
y = mx + b
--> 2 = -1/2*2 +b
--> 2 = -1 + b
Add 1 to both side:
--> 2 + 1 = -1 + b + 1
--> 3 = b
Now to define the equation of the line we substitute in JUST the m and b:
y = mx + b
--> y = -1/2*x + 3
ANSWER