Step one: convert all dimensions to the same units 1km = 1000m therefore 5km = 5000m12km = 12,000mStep two: recall that Pythagoras theorem is used for right angle triangles, defined by the following: a2 + b2 = c2 where c is defined as the hypotenuse, the longest length of the triangleStep three: insert the numbers into the equation (a2 + b2) ----> 132 + 50002 = 25,000,169 (c2) ----------> 120002 = 144,000,000a2 + b2 does not equal c2 therefore not a right angle triangle