Save the game at the top of the slope. Then hop backwards off the edge to slide down the slope facing uphill.
Near the end, hold Action so Lara grabs the end of the slide. Pull up, then briefly release all controls.
Wait a moment for Lara to slip off the edge and then press and hold the Jump button. (Do not press Jump before she falls off the upper slope or she will jump from there and miss the opening to the secret room. Do not press Action or she'll grab, and you don't want that.)
If you hold Jump as she falls onto the short slope, she'll land there and immediately backflip to into the opening of the secret room.
Ta-da!
- OR -
If this doesn't work for you, try this alternate method: Slide backwards down the long slope, holding Action to grab the edge.
Let go then re-press Action to drop onto the shorter slope below, slide...
...and grab the edge.
Pull up onto the short slope...
...and immediately press Jump + Roll + Action together so Lara does a 180 backflip and grabs the doorway to the secret room.
Pull up and you're in.
Pick up the small medi pack (4) and shotgun shells (5), SECRET #2. (NOTE: If you don't already have the SHOTGUN, you'll find it here in place of the shells.)
DARK MODE: Even with brightness adjusted, dark images on a light background can be hard to see. May I suggest a reputable dark mode browser extension, such as Dark Reader? (Download only from trusted sites, like darkreader.org or your browser's web store.)
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