Question

Write the equation of the line that passes through the point (1,-5) and is perpendicular to the line y=1/8x+2.

Answer 1

y = -8x + 3

Explanation:

Step1: find the slope

y = 1/8x + 2

Equation of a line is

y = mx + c

m - slope

From the equation given,

m = 1/8

Note : if two lines are perpendicular to the other, both lines are negative reciprocal of each other

m = -8

Step2 : using the point slope form

y - y1 = m( x - x1)

( 1 , -5)

x1 = 1

y1 = -5

y - (-5) = m( x - 1)

y + 5 = -8(x - 1)

y + 5 = -8x + 8

y = -8x + 8 - 5

y = -8x + 3

The equation of the line is

y = -8x + 3