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Which of the following lines is perpendicular to the line y = -3 x + 2 and passes through the point (–2, 8)?​

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Answer:

y = 1/3x + 26/3

Explanation:

Original equation: y = -3x + 2

Perpendicular lines have the "opposite reciprocal" slopes of each other, meaning you flip the numbers and reverse the sign.

Slope of original equation: -3

Slope of perpendicular line: 1/3

How: Reciprocal, flip the numbers: -3/1 to -1/3, then reverse sign -1/3 to 1/3

Then you substitute (-2, 8) into the new equation: y = 1/3x + b

*there's b because you don't know the y-intercept yet

Substitute: 8 = 1/3(-2) + b

8 = -2/3 + b

Add 2/3 on both sides

b = 24/3 + 2/3

b = 26/3

*this is the y-intercept

Therefore, the perpendicular equation is: y = 1/3x + 26/3

User RedGlow
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