Find the slope of the line through the points P and Q when P=(1,5) , Q=(2,7)
The (x,y) coordinates for the points P and Q are,
P = (1,5) and Q = (2,7)
The slope between these two points, m, is the ratio of the difference between the y-values to the difference between the x-values.
i.e. m = (y1 - y2) / (x1 - x2)
m = (5 - 7) / (1 - 2)
m = (-2) /(-1) = 2 / 1
Answer: slope, m = 2
It doesn't mattter which y-value you take first in the numerator, as long as you take the x-value for the same point first in the denominator.