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13 votes
13 votes
Find the equation of the line that

is perpendicular to y = -4x + 3
and contains the point (8, 1).

User Isatu
by
2.8k points

2 Answers

12 votes
12 votes

Answer:

x-4y=8

Explanation:

y=mx+c comparing with given eq

we get slope(m1)=-4

since both are prependicular

m1×m2=-1

-4×m2=-1

m2=1÷4

eq:-y-y1=m2 (x-x1)

y-1=(1÷4)(x-8)

x-4y=4

User Wkw
by
2.4k points
21 votes
21 votes
y=1/4x-1

perpendicular means the y-intercept stays the same (so 3 stays), but the slope would be the opposite reciprocal of the original.

the opposite of -4 is 4. opposite of negative=positive.

the reciprocal of 4 is 1/4

so the new slope is 1/4

since we have a point, you plus everything on the point slope-form.

y-y1=m(x-x1)

(8,1)—> the 8 is x1 and the 1 is y1
the slope is m

so it’ll be

y-1=1/4(x-8)

solve. first distribute the 1/4

y -1=1/4x - 2

add 1 to both sides

y= 1/4x - 1
User Aditya Thakur
by
2.7k points