A line passes through #(3 ,4 )# and #(4 ,7 )#. A second line passes through #(7 ,3 )#. What is one other point that the second line may pass through if it is parallel to the first line?

1 Answer
Jul 27, 2017

See a solution process below:

Explanation:

First, we need to calculate the slope of the first line: #m_1#. The slope can be found by using the formula: #m = (color(red)(y_2) - color(blue)(y_1))/(color(red)(x_2) - color(blue)(x_1))#

Where #m# is the slope and (#color(blue)(x_1, y_1)#) and (#color(red)(x_2, y_2)#) are the two points on the line.

Substituting the values from the points in the problem gives:

#m_1 = (color(red)(7) - color(blue)(4))/(color(red)(4) - color(blue)(3)) = 3/1#

Because the two lines are parallel, the slope of the second line will also be #3/1#. We can call the slope of the second line #m_2#

Substituting the values from the one point and the slope we calculated for the first line gives:

#m_2 = (color(red)(y) - color(blue)(3))/(color(red)(x) - color(blue)(7))#

#3/1 = (color(red)(y) - color(blue)(3))/(color(red)(x) - color(blue)(7))#

We can now solve these two equations to get another point on the second line:

- Solve for the Numerator:

#y - 3 = 3#

#y - 3 + color(red)(3) = 3 + color(red)(3)#

#y - 0 = 6#

#y = 6#

- Solve for the Denominator:

#x - 7 = 1#

#x - 0 = 8#

One other point on the second line is: #(8, 6)#