Answer:
Part a) The slope of line that passes through the points A (10,4) and B (-2 , -5) is

Part b) The slope of line that passes through the points C (-7 ,1) and D (7, 8) is

Explanation:
Part I: Find the slope of the line that passes through the following points.
Part a)
A (10,4) and B (-2 , -5)
We need to find slope of the line that passes through the given points.
The formula used is:

We can take any two points and the slope will be same.
I am taking points A (10,4) and B (-2 , -5) and finding slope
We have

Putting values and finding slope

So, the slope of line that passes through the points A (10,4) and B (-2 , -5) is

Part a)
C (-7 ,1) and D (7, 8)
We need to find slope of the line that passes through the given points.
The formula used is:

We can take any two points and the slope will be same.
I am taking points C (-7 ,1) and D (7, 8) and finding slope
We have

Putting values and finding slope

So, the slope of line that passes through the points C (-7 ,1) and D (7, 8) is
