A grid shows the positions of a subway stop and your house. The subway stop is located at (–9, 7) and your house is located at (9, –2). What is the distance, to the nearest unit, between your house and the subway stop?
A.25
B. 20
C. 30
D. 17
For this case, the first thing you should do is use the distance between points formula.  We have then:  d = root ((x2-x1) ^ 2 + (y2-y1) ^ 2)  Substituting we have:  d = root ((9 - (- 9)) ^ 2 + (-2-7) ^ 2)  d = 20.1246118  Rounding off we have:  d = 20 units  Answer:  The distance, to the nearest unit, between your house and the subway stop is:  B. 20
