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Passes through the point (-4, -3) and is perpendicular to the line -3x - 4y = 12.

1 Answer

2 votes

Answer:

y=
(4)/(3) x+
(7)/(3)

Explanation:

-3x-4y=12

1. First we need to get the equation in the form of y=mx+c to do this we add 3x to both sides and then divide it by -4 on each side to get

(add 3x to both sides) = -4y=3x+12

(divide each side by -4)= y= -
(3)/(4) x -3

2. to find the perpendicular gradient we find the reciprocal of the original gradient

the reciprocal of -
(3)/(4) is
(4)/(3)

3. we can check this by multiplying them and seeing of we get -1

-
(3)/(4) x
(4)/(3) = = -1

4. we then sub in the gradient
(4)/(3) in y=mx+c this gives us

y=
(4)/(3)x +c

5. to find the value of c we substitute the coordinates into the equation to get ( we do this by expanding the brackets and getting c on it own)

-3=
(4)/(3)(-4) +c

-3= -
(16)/(3) +c


(7)/(3)=c

6. we sub
(7)/(3)=c back into y=
(4)/(3)x +c this gives us

y=
(4)/(3)x +
(7)/(3)

7. Therefore our final answer is

y=
(4)/(3)x +
(7)/(3)

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