SOLUTION: find an equation in standard form of the line: a. through (2,-2) and (4,4) b. perpendicular to y=x+5 and through (0,8)

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: find an equation in standard form of the line: a. through (2,-2) and (4,4) b. perpendicular to y=x+5 and through (0,8)      Log On


   

Question 327203: find an equation in standard form of the line:
a. through (2,-2) and (4,4)
b. perpendicular to y=x+5 and through (0,8)
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
a) Find the slope.
m=%28y2-y1%29%2F%28x2-x1%29=%284-%28-2%29%29%2F%284-2%29=6%2F2=3
Now use the slope intercept form, y=mx%2Bb
y=3x%2Bb
and use either point to solve for b.
4=3%284%29%2Bb
4=12%2Bb
b=-8
highlight%28y=3x-8%29
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Perpendicular lines have slopes that are negative reciprocals.
m1%2Am2=-1
1%2Am2=-1
m2=-1
y=-x%2Bb
Use the point (0,8) to solve for b.
8=0%2Bb
b=8
highlight_green%28y=-x%2B8%29