* Apple, Microsoft and Google set to report results * Tesla rises on strong Q2 earnings * Chinese stocks extend declines * Futures: Dow down 0.24, S&P down 0.14%, Nasdaq up 0.03% (Adds comment, graphic, updates prices) July 27 (Reuters) - U.S. stock indexes were set to open flat on Tuesday ahead of earnings reports from the most valuable companies on Wall Street and in the run-up to the two-day Federal Reserve meeting. More than one third of the S&P 500 is set to report quarterly results this week, led by Apple, Microsoft , Amazon and Google-parent Alphabet, the four largest U.S. companies by market value. Apple, Alphabet and Microsoft, which rose between 0.2% to 0.5% in premarket trade, are set to report earnings after the market closes, while Amazon will report results on Thursday. “The markets may be in a sideways, quiet mode until we get some of those results... generally it’s more reactive than it is proactive,” said Randy Frederick, managing director of Trading and Derivatives at Schwab Center for Financial Research. “The expectations for earnings for growth were high. This is being compared to 2020, when the economy was shut down, and as a result, there’s a very low bar (for comparison).” Investors remained on edge, awaiting more signals from the central bank on when it intends to begin reining in its massive stimulus program. The two-day Fed meeting will begin later in the day. Frederick said the Fed was likely to stand pat on policy this week, but could hint at its plans for tightening during the Jackson Hole Symposium in August. U.S. S&P 500 E-minis were down 6.25 points, or 0.14%, at 08:06 am ET. Dow E-minis were down 84 points, or 0.24%, while Nasdaq 100 E-minis were up 4 points, or 0.03%. Wall Street indexes had inched up to record closing highs on Monday, carrying over momentum from a strong batch of earnings last week. Of the S&P 500 constituents, 124 companies have reported earnings so far and 88.7% of them have beaten estimates, according to Refinitiv data. Electric-car maker Tesla Inc rose 1.4% in premarket trade after it posted a better-than-expected second-quarter profit on higher sales of its less-expensive vehicles. U.S.-listed Chinese stocks extended their declines as fears over more regulations in the mainland persisted. Alibaba and Baidu lost about 3.2% and 4.5%, respectively. General Electric rose more than 4% after it lifted its annual free cash flow forecast after reporting a surprise positive cash flow in the second quarter as industrial orders and revenue returned to growth. Reporting by Ambar Warrick in Bengaluru; Editing by Arun Koyyur Our Standards: The Thomson Reuters Trust Principles.