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Write an equation for the line perpendicular to y=2x 4 that contains (3, -2)?

User Plugie
by
6.9k points

1 Answer

2 votes
in the equation y = 2x + 4, you know that the gradient is 2 (the number before x).


for a perpendicular line you need the negative reciprocal of 2, which is -
(1)/(2) .

you then need to use the equation
y -
y_(1) = m(x -
x_(1) )

substitute in your coordinates:

y - -2 = -
(1)/(2) (x - 3)


simplify:
y + 2 = -0.5x + 1.5

rearrange:

y = -
(1)/(2) x -
(1)/(2)

User Marco Romano
by
7.1k points