\(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfKttLearuGlw5gvP1wzaeXatLxBI9gBam % XvP5wqSXMqHnxAJn0BKvguHDwzZbqegm0B1jxALjhiov2DaeHbuLwB % Lnhiov2DGi1BTfMBaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFf % euY-Hhbbf9v8qqaqFr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9 % q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqaba % WaaqaafaaakqaabeqaaabaaaaaaaaapeWaaSaaa8aabaWdbiabdIha % 4bWdaeaapeGaeG4mamdaaiabg2da9maalaaapaqaa8qacqWG5bqEa8 % aabaWdbiabiwda1aaaaeaacqGHshI3daWcaaqaaiabdIha4jabc6ca % UiabdIha4bqaaiabiodaZaaacqGH9aqpdaWcaaqaaiabdIha4jabc6 % caUiabdMha5bqaaiabiwda1aaaaeaacqGHshI3daWcaaqaaiabdIha % 4naaCaaaleqabaGaeGOmaidaaaGcbaGaeG4mamdaaiabg2da9maala % aabaGaeGOnayJaeGimaadabaGaeGynaudaaaqaaiabgkDiEpaalaaa % baGaemiEaG3aaWbaaSqabeaacqaIYaGmaaaakeaacqaIZaWmaaGaey % ypa0JaeGymaeJaeGOmaidabaGaeyO0H4TaemiEaG3aaWbaaSqabeaa % cqaIYaGmaaGccqGH9aqpcqaIZaWmcqaI2aGnaeaacqGHshI3cqWG4b % aEcqGH9aqpcqaI2aGncqWGObaAcqWGVbWBcqWGHbqycqWGJbWycqWG % 4baEcqGH9aqpcqGHsislcqaI2aGnaeaacqWG4baEcqGH9aqpcqaI2a % GncqGHshI3cqaI2aGncqGGUaGlcqWG5bqEcqGH9aqpcqaI2aGncqaI % WaamcqGHshI3cqWG5bqEcqGH9aqpcqaIXaqmcqaIWaamaeaacqWG4b % aEcqGH9aqpcqGHsislcqaI2aGncqGHshI3cqGHsislcqaI2aGncqGG % UaGlcqWG5bqEcqGH9aqpcqaI2aGncqaIWaamcqGHshI3cqWG5bqEcq % GH9aqpcqGHsislcqaIXaqmcqaIWaamaaaa!A1AE! \begin{array}{l} \frac{x}{3} = \frac{y}{5}\\ \Rightarrow \frac{{x.x}}{3} = \frac{{x.y}}{5}\\ \Rightarrow \frac{{{x^2}}}{3} = \frac{{60}}{5}\\ \Rightarrow \frac{{{x^2}}}{3} = 12\\ \Rightarrow {x^2} = 36\\ \Rightarrow x = 6\,\,hoặc\,\,x = - 6\\ với\,\,x = 6 \Rightarrow 6.y = 60 \Rightarrow y = 10\\ với\,\,x = - 6 \Rightarrow - 6.y = 60 \Rightarrow y = - 10 \end{array}\)