How to Read Trend Lines and Support and Resistance Like a Technical Analyst

Long before anyone had a laptop, let alone a phone, traders were drawing lines across hand plotted price charts to figure out where a stock was likely to find buyers or sellers. The idea got its modern, widely taught treatment from John Murphy, whose book "Technical Analysis of the Financial Markets" has introduced several generations of traders to the basic toolkit of chart reading. Trend lines, along with support and resistance, sit right at the center of that toolkit, and they remain one of the first things most people learn when they start looking at charts seriously.

The appeal is simple. A trend line is just a straight line connecting a series of price points, usually swing lows in an uptrend or swing highs in a downtrend, that shows the general direction and pace of a move. Support is a price area where a stock has tended to stop falling and turn back up. Resistance is the mirror image, a price area where a stock has tended to stop rising and turn back down. None of this requires a formula, a subscription, or a computer science degree. It requires a chart and a willingness to look at it honestly.

That last part, honesty, is really the whole game, and it is why this concept is still genuinely useful more than three decades after Murphy first wrote about it. A trend line is only as good as the swing points it is drawn from, and a huge amount of bad trading comes from traders bending a line to fit what they want to see rather than what the chart is actually showing. This week we will build a real, split adjusted trend line on NVDA stock, watch it get tested, watch it actually break, and then watch it get reclaimed, all using real weekly price data rather than a tidy textbook drawing.

What a Trend Line Actually Is, and How to Read One

Start with the raw ingredients: a swing low is a week (or day, depending on your timeframe) where the price dropped and then turned back up, so that the low of that week sits below the lows of the weeks on either side of it. A swing high is the opposite, a week where the high sits above the highs around it. These turning points are the chart's own record of where buyers or sellers actually stepped in.

To draw a rising support trend line, a technical analyst looks for at least two swing lows that are both higher than the one before, then connects them with a straight line and extends that line forward into the future. The logic is that if buyers have twice shown up around a rising price level, they may show up there again. A falling resistance trend line works the same way in reverse, connecting a series of lower swing highs.

Two touches is the minimum to draw a line. Three or more touches, especially if they are spread out over weeks or months rather than clustered together, is what gives a trend line real credibility. A line drawn through two points that happen to line up by coincidence is not much more than a guess; a line that price has respected three or four separate times, across different market conditions, is telling you something about how that particular stock is being traded.

The other habit worth building early is distinguishing a wick from a close. Weekly candlestick charts show four prices for the week: the open, the close, and the high and low, usually drawn as a thin line (the "wick" or "shadow") extending above and below a thicker body. Price can dip below a trend line on a wick, meaning it traded there briefly during the week, without actually breaking the trend. What matters more to most technical analysts is where the price closed. A single week that closes back above a trend line after dipping below it on a wick is usually read as the trend line holding, or being "tested" successfully. Multiple weeks in a row closing below the line is a much stronger signal that the trend line has genuinely broken, sometimes called a "breakdown."

A Real Trend Line on NVDA, Start to Finish

Here is the whole sequence, built entirely from real weekly OHLCV data pulled this week and adjusted for NVDA's stock splits so the chart is not distorted by the mechanical price drop a split causes. The first swing low used to anchor the line sits in the week of September 5, 2025, at a low of $164.07. The second sits in the week of November 28, 2025, at a low of $169.55, higher than the first. Two points, both higher than the last, is enough to draw the line and project it forward.

The first real test came in the week of February 6, 2026. The weekly low that week was $171.03, which actually dipped slightly below where the projected trend line sat at that point ($174.12), but the week closed at $185.41, well above the line. By the "close, not wick" standard most technical analysts use, that is a trend line holding, not breaking. This is exactly the kind of moment that separates a careful trend line reader from someone who panics at the first lower wick they see.

Then, in late March 2026, something more serious happened. Over the three weeks of March 20, March 27, and April 2, 2026, NVDA closed at $172.70, $167.52, and $177.39, all below where the trend line sat during those weeks (roughly $176.86 to $177.77). Three consecutive closes below the line is a real break by almost any reasonable definition, not a wick, not a one week fluke. If you were following this trend line in real time, this is the point at which you would reasonably conclude the rising support had failed.

Except it was not over. The very next week, April 10, 2026, NVDA closed at $188.63, decisively back above the trend line, which by then sat near $178.23. The breakdown had failed to follow through, and the stock went on to make a new higher low in the week of July 2, 2026, at $189.80, still above the trend line and consistent with the original uptrend. As of the most recent close in this data set, October 23, 2026, NVDA closed at $210.96, while the same trend line, extended all the way out, sits near $191. More than a year after it was first drawn from two swing lows, the line is still technically intact, even though price broke below it on a closing basis for a few weeks along the way.

This is a genuinely useful, if slightly messy, real world lesson. Murphy's own writing on trend lines is clear that a line is a tool for organizing your thinking about a trend, not a guarantee, and that both false tests and false breaks happen regularly. The NVDA example above has both: a false test in February (the wick below, close above), and what looked like a real break in March and April that ultimately reversed. Reading a trend line well means being able to sit with that kind of ambiguity instead of forcing a clean story onto the data.

A Closer Look, With a Hypothetical Trade Example

Chart 2: A zoomed in view of the same NVDA trend line from October 2025 through July 2026, isolating the February test, the March to April break, and the April reclaim, with a hypothetical entry, stop, and target overlaid for illustration.

Zooming in on the test, break, and reclaim makes the sequence easier to see week by week. It also lets us walk through a HYPOTHETICAL way a trend line follower might have approached this setup. This is not a recommendation and not a claim about what any real trader did; it is purely an illustration of how the concept connects to a trading decision.

HYPOTHETICAL example: suppose a trader waited for confirmation rather than acting on the first dip below the line, and bought NVDA on the close of April 10, 2026 at $188.63, the week the stock reclaimed the trend line after the three week break. A reasonable, structurally based stop loss would sit below the broken low from that sequence, around $163, giving the trade room to breathe without ignoring the possibility that the breakdown was real after all. A first target might be set near the next visible resistance zone from recent chart history, around $230. Again, this entire paragraph is a hypothetical illustration built after the fact to show how the pieces fit together, not a performance claim or investment advice.

Notice what this example does and does not do. It does not try to catch the exact bottom of the dip in March, which is usually a low probability bet. It waits for the close to confirm that buyers had stepped back in, which costs some upside but avoids acting on noise. That tradeoff, giving up the first few dollars of a move in exchange for more confidence that the move is real, is one of the central judgment calls in trend line trading.

A Checklist Before You Act on a Trend Line

• Does the line actually connect at least two, and ideally three or more, real swing lows or swing highs, rather than being drawn to pass near one or two candles that do not clearly stand out as turning points?
• Are you judging a "break" by the closing price over multiple periods, not by a single wick poking through the line for a few hours or one week?
• Does the trend line agree with what the stock is doing on a higher timeframe (for example, does a weekly support line sit in roughly the same place as a monthly one), or is it only visible if you zoom in tightly?
• Have you checked whether volume increased on the move that tested or broke the line, since a break on unusually heavy volume generally carries more weight than one on a quiet week?
• Do you already know, before you act, exactly where you would be wrong, meaning a specific stop loss level, rather than deciding that after the trade is already open?

Limits and Risks

Trend lines are a useful organizing tool, not a precise predictive instrument, and it is worth being direct about that. Because they are drawn by a human (or by software following rules a human set), two careful chart readers can draw slightly different lines on the exact same chart and reach different conclusions about whether it has broken. The NVDA example above shows a trend line that was "broken" for a few weeks before resuming its climb; a trader who treated that break as final and exited or shorted the stock would have been faked out, at least for this particular stretch of 2026.

False breaks and false tests happen in both directions, and there is no setting or rule that eliminates them entirely. Trend lines also tend to work better in trending markets than in choppy, sideways ones, where price can cross back and forth over a line repeatedly without either side ever really winning. For these reasons, most experienced chart readers treat a trend line as one input among several, combining it with other forms of confirmation such as volume, momentum indicators, or the broader market environment, and they manage risk with a predefined stop rather than assuming any single line will hold. No pattern or indicator in technical analysis works every time, and trend lines are no exception.

Try it yourself on TruCharts. The interactive stock charts at trucharts.com let you draw and test your own trend lines directly on real price history, including NVDA. Pull up the same stretch of 2025 and 2026 covered in this article, add the line tool, and see for yourself where the test, the break, and the reclaim sit, before scrolling forward to see what actually happened next. It is a much better way to build the habit of reading closes instead of wicks than staring at a static image.

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Coming up next week: we will look at reading momentum rather than price directly, covering how to spot bullish and bearish divergence using RSI and MACD, an idea most closely associated with Martin Pring's book "Technical Analysis Explained." Read next week's article once it is live.

This article is for educational and informational purposes only and does not constitute financial or investment advice. Any hypothetical trade examples described above are clearly labeled as hypothetical and are not a record of actual trades or guaranteed outcomes. Past price behavior, including the NVDA example used here, does not predict future results. Please consult a licensed financial advisor before making any investment decisions.