Monday, July 27, 2009

practice for slope and slope intercept from point slope

1a) Find the slope of the line that passes through (1, 5) and (4, -7).
1b) Find the slope intercept version of the linear equation for this line.

2a) Find the slope of the line that passes through (1, 0) and (4, 0).
2b) Find the slope intercept version of the linear equation for this line.

3a) Find the slope of the line that passes through (1, 4) and (1, -7).
3b) Find the slope intercept version of the linear equation for this line.

Answers in the comments.

1 comment:

Prof. Hubbard said...

1a) Find the slope of the line that passes through (1, 5) and (4, -7).

Slope = (5-(-7))/(1-4) = 12/-3 = -4.

1b) Find the slope intercept version of the linear equation for this line.

Using the point (1, 5), we have

y - 5 = -4(x - 1)
Clearing parentheses.
y - 5 = -4x + 4
Adding 5 to both sides.
y = -4x + 9


2a) Find the slope of the line that passes through (1, 0) and (4, 0).

Slope = (0-0)/(1-4) = 0/-3 = 0.


2b) Find the slope intercept version of the linear equation for this line.

Using the point (1, 0), we have

y - 0 = 0(x - 1)
Clearing parentheses.
y - 0 = 0
Adding 5 to both sides.
y = 0


3a) Find the slope of the line that passes through (1, 4) and (1, -7).

Slope = (4-(-7)/(1-1) = 11/0 = undefined.

3b) Find the slope intercept version of the linear equation for this line.

There isn't a slope intercept version. The equation of the line is that x equals a constant, in this case x = 1.