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Write an equation for a line perpendicular to y=1/4x−3 and passing through the point (4,1)

User Myo
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1 Answer

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y = 1/4 x - 3

First. find the slope of the above equation

To do that, we will compare the above equation with y = mx + b

where m is the slope and b is the intercept

m = 1/4

Now, note that;

slope of perpendicular equations are inverse of each other

That is;

m₁m₂ = -1

substitute m₁= 1/4 and then solve for m₂

1/4 m₂ = -1

multiply both-side of the equation by 4

m₂ = -4

The slope of our new equation is -4

We will now go ahead to find the intercept b of the new equation

To do that, substitute x = 4 y=1 and m=-4 into y =mx + b and then solve for b

1 = -4(4) + b

1 = -16 + b

add 16 to both-side of the equation

1 + 16 = b

17 = b

b = 17

To form the new equation, simply substitute m = -4 and b = 17 into y=mx+b

The equation is:

y = -4x + 17

User Greybeard
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