Final answer:
Margaret Thatcher aimed to achieve economic growth, reduce unemployment, and maintain low inflation as her main economic objectives upon taking office in 1979.
Step-by-step explanation:
Margaret Thatcher's three main economic objectives when she took office in 1979 were to achieve economic growth, secure low unemployment, and maintain low inflation. These goals are at the heart of macroeconomic policy and are essential for the overall health of an economy. Thatcher, similar to Ronald Reagan in the United States, implemented policies to stimulate the economy that included cutting government programs and taxes, advocating for free-market capitalism, and deregulating industries.