Line k passes through the point (1, 5) and is perpendicular to the line y = 3x + 1. Which of the following points does line k also pass through?

Select one:
A. (4, 4)
B. (-2, -5)
C. (3, 6)
D. (9, -1)

Respuesta :

Answer:

Option A. (4,4)

Step-by-step explanation:

step 1

Find the slope of the line k

we know that

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

[tex]m1*m2=-1[/tex]

The slope of the given line is [tex]m1=3[/tex]

so

The slope of the line k is

[tex]m2*(3)=-1[/tex]

[tex]m2=-\frac{1}{3}[/tex]

step 2

Find the equation of the line k

The equation of the line into point slope form is equal to

[tex]y-y1=m(x-x1)[/tex]

we have

[tex]m=-\frac{1}{3}[/tex]

[tex]point(1,5)[/tex]

substitute the values

[tex]y-5=-\frac{1}{3}(x-1)[/tex]

step 3

Verify if the line k pass through the given points

Remember that

If the line passes through a point, then the value of x and the value of y of the point must satisfy the equation of the line

Verify each case

case A) (4,4)

[tex]4-5=-\frac{1}{3}(4-1)[/tex]

[tex]-1=-\frac{1}{3}(3)[/tex]

[tex]-1=-1[/tex] ----> is true

therefore

The line k pass through the point (4,4)

case B) (-2,-5)

[tex]-5-5=-\frac{1}{3}(-2-1)[/tex]

[tex]-10=-1[/tex] -----> is not true

therefore

The line k not pass through the point (-2,-5)

case C) (3,6)

[tex]6-5=-\frac{1}{3}(3-1)[/tex]

[tex]1=-\frac{2}{3}[/tex] -----> is not true

therefore

The line k not pass through the point (3,6)

case D) (9,-1)

[tex]-1-5=-\frac{1}{3}(9-1)[/tex]

[tex]-6=-\frac{8}{3}[/tex] -----> is not true

therefore

The line k not pass through the point (9,-1)