In x-y plane, there is a right triangle ABC (∠B=90o). If the length of AC is 100 and the slope of line segment AC is 4/3, what is the length of AB?
Answers: A) 12 B) 18 C) 24 D) 28 E) 80

Rationale: slope = change in vertical direction / change in horizontal direction = 4 / 3 change in vertical direction = 4 x = ab change in horizontal direction = 3 x = bc ab ^ 2 + bc ^ 2 = 100 ^ 2 16 x ^ 2 + 9 x ^ 2 = 10000 25 x ^ 2 = 400 x ^ 2 = 400 x = 20 therefore ab = 20 * 4 = 80 answer : e
Answer: E