MathDB
Positive integer solution

Source: 2018 Taiwan APMO preliminary

November 10, 2020
algebra

Problem Statement

Let a,ba,b be positive integers satisfying ab2b2a=a+2b4b\sqrt{\dfrac{ab}{2b^2-a}}=\dfrac{a+2b}{4b}. Find 10(a5)(b15)+8|10(a-5)(b-15)|+8.