Question

Write an equation of the line that is perpendicular to y = 1/2x + 3 and passes through the point (10, -5).

A) y = -2x + 15
B) y = 2x - 15
C) y = -2x - 5
D) y = - 1/2x
Please Help me :)

Answer 1

It's A) y = -2x + 15 i just took the test

Explanation:

Answer 2

Option A) y = -2x + 15

Explanation:

step 1

Find the slope of the line perpendicular to the given line

we know that

If two lines are perpendicular, then their slopes are opposite reciprocal (the product of their slopes is equal to -1)

The equation of the given line is

`y=(1)/(2)x+3`

so

The slope of the given line is
`m=(1)/(2)`

therefore

The slope of the line perpendicular to the given line is

`m=-2`

step 2

Find the equation of the perpendicular line in point slope form

`y-y1=m(x-x1)`

we have

`m=-2`

`point\ (10,-5)`

substitute

`y+5=-2(x-10)` ---> equation in point slope form

Convert to slope intercept form

`y=mx+b`

`y+5=-2x+20`

`y=-2x+20-5`

`y=-2x+15`