SOLUTION: what is the equation of a line that passes through (-7, 1) and is parallel to y = x + 4 what is the equation of a line that passes through (4, 2) and is perpendicular to y = 1/2

Algebra ->  Linear-equations -> SOLUTION: what is the equation of a line that passes through (-7, 1) and is parallel to y = x + 4 what is the equation of a line that passes through (4, 2) and is perpendicular to y = 1/2      Log On


   

Question 841368: what is the equation of a line that passes through (-7, 1) and is parallel to y = x + 4
what is the equation of a line that passes through (4, 2) and is perpendicular to y = 1/2x + 1
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Parallel lines have identical slopes.
y=x%2Bb
Use the point to solve for b
1=-7%2Bb
b=8
highlight%28y=x%2B8%29
.
.
Perpendicular line slopes are negative reciprocals.
m%5B1%5D%2Am%5B2%5D=-1
%281%2F2%29%2Am%5B2%5D=-1
m%5B2%5D=-2
y=-2x%2Bb
Again use the point to solve for b
2=-2%284%29%2Bb
2=-8%2Bb
b=10
highlight%28y=2x%2B10%29