What is the perimeter of ABC with vertices A (-2,9) , B (7,-3) , C (-2,-3) in the coordinate plane? A. 21 units
B. 15 units
C. 34 units
D. 36 units

9514 1404 393

  D.  36 units

Step-by-step explanation:

Using the distance formula, we find the length of AB to be ...

  d = √((x2 -x1)² +(y2 -y1)²)

  d = √((7-(-2))² +(-3-9)²) = √(81 +144) = √225 = 15

The line BC is horizontal, so its length is the difference of the x-coordinates:

  BC = 7 -(-2) = 9

The line AC is vertical, so its length is the difference of the y-coordinates:

  AC = 9 -(-3) = 12

The sum of the lengths of the sides of the triangle is ...

  P = 15 + 9 + 12 = 36

The perimeter is 36 units.

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.

the answer is 31.27mph