Question

Find the equation of the line that is perpendicular to the given line and passes through the given point.

y = −
1
5
x − 2; (11, 0)

The equation is y=

Answer 1

Answer:

y = 3x + 2

y = 6x – 3

y = 2/3x + 6

y = –1/3x – 4

y = 2x + 1

Correct answer:

y = 3x + 2

Explanation:

Convert the equation to slope intercept form to get y = –1/3x + 2.  The old slope is –1/3 and the new slope is 3.  Perpendicular slopes must be opposite reciprocals of each other:  m1 * m2 = –1

With the new slope, use the slope intercept form and the point to calculate the intercept: y = mx + b or 5 = 3(1) + b, so b = 2

So y = 3x + 2