Question

What is the equation of a line that passes through the point (1, 8) and is perpendicular to the line whose equation is y = x/2 + 3 ?

Enter your answer in the box.

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Answer 1

y = - 2x + 10

the equation y =
`(1)/(2)` x + 3 is in slope- intercept form

with slope m =
`(1)/(2)`

given a line with slope m then the slope of a line perpendicular to it is m₂ = -
`(1)/(m)`

perpendicular slope = - 2

partial equation is y = - 2x + c

to find c substitute (1, 8 ) into the partial equation

8 = - 2 + c ⇒ c = 8 + 2 = 10

y = - 2x + 10 ( equation in slope-intercept form )