|ax+b|+|cx+d|=|ex+f| - All-Russian MO 2001 Regional (R4) 8.5
Source:
September 25, 2024
algebra
Problem Statement
Let a,b,c,d,e and f be some numbers, and a⋅c⋅e=0.It is known that the values of the expressions ∣ax+b∣+∣cx+d∣and ∣ex+f∣ equal at all values of x. Prove that ad=bc.