232k views
5 votes
Which point on the x-axis lies on the line that passes through point P and is perpendicular to line MN?

(0, 1)
(0, 4)
(1, 0)
(4, 0)

Which point on the x-axis lies on the line that passes through point P and is perpendicular-example-1
User Cipi
by
8.1k points

2 Answers

2 votes
the answer is C. (1,0)
User Moler
by
8.0k points
3 votes

1. Points M and N have coordinates (-4,0) and (4,2), respectively.

Then vector
\overrightarrow{MN}=(4-(-4),2-0)=(8,2) is perpendicular to the neede line.

2. Write the equation of line that passes through the point P(2,-4) and is perpendicular to vector
\overrightarrow{MN}=(8,2):


8(x-2)+2(y+4)=0,\\8x-16+2y+8=0,\\8x+2y-8=0,\\4x+y-4=0.

3. Find the point on x-axis, that lies on the perpendicular line.

When y=0, then 4x-4=0, x=1 and point (1,0) lies on perpendicular line.

Answer: correct choice is C.

User Jeff Beagley
by
7.4k points