Question

Consider the graph of the line y = x – 4 and the point (−4, 2).

Answer 1

Answer:

a. The slope  of a line parallel to the given line is 1

b. A point on the line parallel to the given line, passing through (−4, 2), is  (1,7)

c. The slope of the line perpendicular to the given line is -1

d. A point on the line perpendicular to the given line, passing through (−4, 2), is (3,-5)

Step-by-step explanation:

The equation of the line in Slope-intercept form  is:

$y=mx+b$

Where m is the slope and b is the y-intercept.

a. For the line $y = x - 4$

You can identify that:

$m=1$

 By definition, two lines are parallel if they have the same slope. Then, the  slope of a line parallel to the given line is:

$m=1$

b. The equation of the line in Point-slope form is:

$y -y_1 = m(x - x_1)$

Where m is the slope and ($x_1,y_1$)  is a point of the line.

Given the point (-4,2), substitute this point and the slope of the line into the equation:

 $y -2 = (x +4)$

Give a value to "x", substitute it into this equation and solve for "y":

For $x=1$ :

$y -2 = (1 +4)$

$y= 5+2$

$y= 7$

Then, you get the point (1,7)

c. The slopes of perpendicular lines are negative reciprocals, then the  slope of a line perpendicular to the given line is:

$m=-\frac{1}{1}\\\\m=-1$

d. Given the point (-4,2), substitute this point and the slope of the line into the equation:

 $y -2 = -1(x +4)$

 $y -2 = -(x +4)$

Give a value to "x", substitute it into this equation and solve for "y":

For $x=3$ :

$y -2 = -(3 +4)$

$y= -7+2$

$y= -5$

Then, you get the point (3,-5)