Question

What is the slope of the line passing through the point (4, −2) and perpendicular to the line y = 4x + 2? Write your answer as a fraction.

Answer 1

what's the slope of the y = 4x +2?

Answer 2

The slope of the line y = 4x + 2 is 4.
Let the unknown slope = m
The product of the two slopes must equal -1 if the two lines are perpendicular.
4m = -1 .............(1)
Can you solve equation (1) to find the value of m ?

Answer 3

im not sure

Answer 4

y = 4x + 2
^
slope

as kropot72 already pointed out

Answer 5

Formula is y=mx+c
so here the question is y = 4x + 2
so 4 is the slope :)

Answer 6

4m = -1
What do you get if you divide both sides by 4 ?

Answer 7

-4

Answer 8

What is 4m/4 ?
\[\frac{4m}{4}=?\]

Answer 9

1

Answer 10

No.
\[\frac{4}{4}=1\]
\[\frac{4m}{4}=?\]

Answer 11

m?

Answer 12

perpendicular lines, have "negative reciprocal slopes", so
if one function has a slope of "4"
reciprocal of 4 = 1/4
negativize that = -(1/4)

so, that'd be the negative reciprocal of "4", and thus the slope of the 1st function which passes through (4, -2)

Answer 13

so its 1/4?

Answer 14

or -1/4 i mean

Answer 15

or 4m = -1 => m = -1/4

as kropot72 indicated

Answer 16

ok thanks !

Answer 17

now, use your slope and the points it passes through to get the function, using the point-slope form

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