the equation is currently y = 1/2 x + 1. How does the equation affect the slope's position vs its angle

3 answers

The equation you provided, \( y = \frac{1}{2}x + 1 \), is in the slope-intercept form, \( y = mx + b \), where \( m \) is the slope and \( b \) is the y-intercept.

  1. Slope: The slope of the line is given by the coefficient of \( x \), which in this case is \( \frac{1}{2} \). The slope indicates how steep the line is. A slope of \( \frac{1}{2} \) means that for every 1 unit increase in \( x \), \( y \) increases by \( \frac{1}{2} \) units. This results in a line that rises gently as it moves to the right.

  2. Angle: The angle of the line with respect to the positive x-axis can be determined from the slope. The relationship between slope \( m \) and angle \( \theta \) is given by the tangent function: \[ m = \tan(\theta) \] To find the angle, you can use: \[ \theta = \tan^{-1}(m) \] For your equation: \[ \theta = \tan^{-1}\left(\frac{1}{2}\right) \] This can be calculated to find the angle the line makes with the x-axis.

  3. Position vs. Angle: The position of the line is defined by its y-intercept \( b \) (which is 1 in your equation). This means that the line intersects the y-axis at (0, 1). Changing the slope (the steepness of the line) affects the angle with which it ascends or descends in relation to the x-axis but does not affect the y-intercept. Conversely, changing the y-intercept simply shifts the line up or down without changing its angle.

In summary:

  • The slope determines the steepness and angle of the line.
  • The y-intercept determines the position of the line on the y-axis.
  • The angle can be calculated from the slope and indicates how "tilted" the line is.
I dont really understand, id like to change the tilt of the line to between (13, 9) and (3, 3)

To find the equation of a line that passes through two specific points, you first need to calculate the slope and then use the point-slope form of the line equation.

Step 1: Calculate the Slope

Given the points \((3, 3)\) and \((13, 9)\), you can calculate the slope \( m \) using the formula:

\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

Plugging in the values:

\[ m = \frac{9 - 3}{13 - 3} = \frac{6}{10} = \frac{3}{5} \]

Step 2: Write the Equation of the Line

Now that we have the slope, we can use the point-slope form of the equation, which is given by:

\[ y - y_1 = m(x - x_1) \]

You can use either point, but let's use \((3, 3)\):

\[ y - 3 = \frac{3}{5}(x - 3) \]

Step 3: Simplify to Slope-Intercept Form

Distributing the slope:

\[ y - 3 = \frac{3}{5}x - \frac{9}{5} \]

Now, add 3 (which is \(\frac{15}{5}\) when expressed with a common denominator) to both sides to solve for \(y\):

\[ y = \frac{3}{5}x - \frac{9}{5} + \frac{15}{5} \]

\[ y = \frac{3}{5}x + \frac{6}{5} \]

Final Equation

So, the equation of the line that passes through the points \((3, 3)\) and \((13, 9)\) is:

\[ y = \frac{3}{5}x + \frac{6}{5} \]

Understanding Tilt and Position

  • Tilt (Slope): The slope \(\frac{3}{5}\) indicates the tilt of the line. For every 5 units you move to the right (increase in \(x\)), the line rises by 3 units (increase in \(y\)).
  • Position (Y-Intercept): The y-intercept is \(\frac{6}{5}\) or \(1.2\), which is where the line crosses the y-axis.

This new line will have the desired tilt between the given points. If you graph the two points and draw the line connecting them, it will represent the equation you derived.