After school, Edwin skateboards directly from school to a skate park and then from the skate park to a candy store. The skate park is 9 kilometers south of the school and the candy store is 12 kilometers east of the skate park. What is the straight-line distance between the school and the candy store?(Pythagorean theorem)
First, we need to calculate the distance between the school and the candy store using the Pythagorean theorem, which states that in a right triangle, the square of the length of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the lengths of the other two sides.
Let's denote the distance between the school and the skate park as side a (9 km) and the distance between the skate park and the candy store as side b (12 km). The straight-line distance between the school and the candy store will be the length of the hypotenuse, denoted as side c.
a^2 + b^2 = c^2
(9)^2 + (12)^2 = c^2
81 + 144 = c^2
225 = c^2
c = √225
c = 15 km
Therefore, the straight-line distance between the school and the candy store is 15 kilometers.