Which expression represents the number of possible combinations of n items taken r at a time?

Step-by-step explanation:

Given :Total items = n

           Items taken at a time = r

To Find: Which expression represents the number of possible combinations of n items taken r at a time?

Solution:

We will use combination over here.

Now Total items = n

         Items taken at a time = r

Thus expression represents the number of possible combinations of n items taken r at a time is

b

step-by-step explanation:

calculate the scale factor as the ratio of corresponding sides, image to original, that is

scale factor = = = = 1

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)