If you think of an exponent as signifying repeated multiplication, the rules of exponents may be easier to remember. The exponent tells you how many times the base is a factor in the product.
Consider multiplication:
Consider division:
This may help you see that a positive exponent in the denominator is equivalent to a negative exponent in the numerator (and vice versa).
The distance between the house and the subway is given by: d=√[(x-x1)²+(y-y1)²] Thus given the coordinates: (-1,9) and (2,-4) thus d=√[(2-(-1))²+(-4-9)²] d=√[(3)²+(-13)²] d=√[9+169] d=√178 d=13.34 ~13 units Answer: D) 13