Question

Write an equation of a line perpendicular to the line 1/2x - 5 , passing through the point (-1 , 7)

Answer 1

Answer ↓

y=-2x+5

Calculations ↓

First of all we need to determine the slope of the line perpendicular to y = 1/2x - 5 .

The slopes of perpendicular lines are opposite reciprocals.

So we take 1/2 , turn it over , and change it's sign :

$^1/_2\:\:\:--- > ^2/_1\:\:\:--- > 2\:\:\:--- > -2$

The slope of the line perpendicular to y = 1/2x-5 is -2 .

Since we're also given a point that the line crosses , we can write the line's equation in point - slope form :

y-y₁=m(x-x₁)

y-7=-2(x-(-1)

y-7=-2(x+1)

Now convert to slope intercept :

y-7=-2x-2

add 7 on both sides :

y = -2x+5

$\footnotesize\text{hope\:helpful}$