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6 votes
6 votes
Through (4,-9) perpendicular to 8y=x-16

User Brad Herman
by
2.7k points

1 Answer

20 votes
20 votes

Answer:

y = -8x + 23

Explanation:

8y=x-16

we need to turn this into slope-intercept form by dividing 8 on both sides

y = x/8 - 2

to make a line perpendicular from another, we must make sure the slope is the negative reciprocal of the original line.

Right now, it's the same as the original. To make it a negative reciprocal, switch the places of the denominator and numerator and flip the signs

-8x is the negative reciprocal of x/8

Does it go through (4,-9)? No.

To make sure it goes through 4,-9, we change it's y-intercept.

Plug in the coordinate given (4,-9) in the y = -8x + b ( we removed -2 since it's not the right answer.

y = -8x + b

(-9) = -8(4) + b

-9 = -32 + b

-9 +32= -32 + b +32

23 = b

plug in b and we get our answer

y = -8x + 23

User Dynite
by
2.6k points
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