Find the slope of the segment with the endpoints (1, − 1/n ) and ( n/m , − 1/m ).

(y - yo) = m.(x - xo)

Let's go

(-1/n - (-1/m)) = s.(1 - n/m)

(-1/n + 1/m) = s.(1 - n/m)

(-m+n)/mn = s.(m - n)/m

If we multiply both sides by m

(-m + n)/n = s.(m - n)

If we take the (-1) from the left side we have

(-1.(m - n))/n = s.(m - n)

And if we divide both sides by (m - n)

-1/n = s

So our slope is -1/n

question:

could we have options?

to find the total number of combinations, multiply the quantity of each item by each other:

2 pairs of shoes x 3 pairs of shorts = 6 different combinations.