How do you find the slope of the line containing points with the coordinates (-4, -5) and (4, 4)?

1 Answer
Mar 19, 2018

#+9/8#

Explanation:

Slope (gradient) is all about rate of change.

You always read left to right on the x-axis (unless stated otherwise)

The left most #x# is the -4

Set point 1 as #P_1->(x_1,y_1)=(-4,-5)#

Set point 2 as #P_2->(x_2,y_2)=(4,4)#

Slope (gradient) is the change in up or down for a given amount of along.

If the change is down then the gradient is negative.
If the change is up then the gradient is positive.

Gradient is #P_2-P_1 ->("change in up or down")/("change in along") =(y_2-y_1)/(x_2-x_1)#

Set gradient as #m=(y_2-y_1)/(x_2-x_1)= (4-(-5))/(4-(-4)) =(4+5)/(4+4)=+9/8#

Tony B