SOLUTION: The line through (2,1) and (-3,n) has a gradient of -4. Find n

Algebra ->  Length-and-distance -> SOLUTION: The line through (2,1) and (-3,n) has a gradient of -4. Find n      Log On


   

Question 803540: The line through (2,1) and (-3,n) has a gradient of -4. Find n
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
The line through (2,1) and (-3,n) has a gradient of -4.
Find n:
y=mx%2Bb....use slope-intercept form to find equation of a line with a slope
m=-4
y=-x%2Bb........use point (2,1) to find y-intercept b
1=-2%2Bb
b=3
so, your equation is:
y=-x%2B3
and plug in point (-3,n)
n=-%28-3%29%2B3
n=+3%2B3
n=6
so, your point is at (-3,n) =(-3,6) and both points, (2,1) and (-3,6) lie on a line