To find the equation of a line that is perpendicular to the given line \(y = 3x + 4\) and passes through the point \((2, -1)\), we need to follow these steps:
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Find the slope of the given line. The slope from the equation \(y = 3x + 4\) is \(3\).
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The slope of a line that is perpendicular to another line is the negative reciprocal of the original slope. Therefore, the perpendicular slope \(m\) is given by:
\[ m = -\frac{1}{3} \]
- Now we will use the point-slope form of the equation of a line, which is:
\[ y - y_1 = m(x - x_1) \]
where \((x_1, y_1)\) is the point \((2, -1)\). Plugging in the values:
\[ y - (-1) = -\frac{1}{3}(x - 2) \]
- Simplifying this, we have:
\[ y + 1 = -\frac{1}{3}x + \frac{2}{3} \]
- Now, subtracting \(1\) (which is equivalent to \(\frac{3}{3}\)) from both sides gives:
\[ y = -\frac{1}{3}x + \frac{2}{3} - \frac{3}{3} \] \[ y = -\frac{1}{3}x - \frac{1}{3} \]
- Thus, the equation of the line we are looking for is:
\[ y = -\frac{1}{3}x - \frac{1}{3} \]
Now, looking at the provided response options, the equation that matches this formula is:
y is equal to negative one third x minus one third.