Given [tex]\( G (3, -1) \)[/tex] and [tex]\( H (-9, 7) \)[/tex], what is the slope of line [tex]\( GH \)[/tex]?

Please show your work and explain your thinking.



Answer :

To find the slope of the line passing through the points [tex]\( G(3, -1) \)[/tex] and [tex]\( H(-9, 7) \)[/tex], we will follow these steps:

1. Identify the coordinates of points [tex]\( G \)[/tex] and [tex]\( H \)[/tex].
2. Calculate the change in [tex]\( y \)[/tex]-coordinates ([tex]\(\Delta y\)[/tex]).
3. Calculate the change in [tex]\( x \)[/tex]-coordinates ([tex]\(\Delta x\)[/tex]).
4. Use the formula for the slope of a line, [tex]\( m \)[/tex], which is given by:

[tex]\[ m = \frac{\Delta y}{\Delta x} \][/tex]

Let's go through each step in detail:

### Step 1: Identifying the coordinates
- Point [tex]\( G \)[/tex] has coordinates [tex]\( (3, -1) \)[/tex]:
- [tex]\( x_1 = 3 \)[/tex]
- [tex]\( y_1 = -1 \)[/tex]

- Point [tex]\( H \)[/tex] has coordinates [tex]\( (-9, 7) \)[/tex]:
- [tex]\( x_2 = -9 \)[/tex]
- [tex]\( y_2 = 7 \)[/tex]

### Step 2: Calculate the change in [tex]\( y \)[/tex]-coordinates ([tex]\(\Delta y\)[/tex])
The change in [tex]\( y \)[/tex]-coordinates ([tex]\(\Delta y\)[/tex]) is found by subtracting the [tex]\( y \)[/tex]-coordinate of point [tex]\( G \)[/tex] from the [tex]\( y \)[/tex]-coordinate of point [tex]\( H \)[/tex]:

[tex]\[ \Delta y = y_2 - y_1 = 7 - (-1) = 7 + 1 = 8 \][/tex]

### Step 3: Calculate the change in [tex]\( x \)[/tex]-coordinates ([tex]\(\Delta x\)[/tex])
The change in [tex]\( x \)[/tex]-coordinates ([tex]\(\Delta x\)[/tex]) is found by subtracting the [tex]\( x \)[/tex]-coordinate of point [tex]\( G \)[/tex] from the [tex]\( x \)[/tex]-coordinate of point [tex]\( H \)[/tex]:

[tex]\[ \Delta x = x_2 - x_1 = -9 - 3 = -12 \][/tex]

### Step 4: Calculate the slope ([tex]\( m \)[/tex])
Now, we will use the slope formula:

[tex]\[ m = \frac{\Delta y}{\Delta x} = \frac{8}{-12} \][/tex]

Simplify the fraction:

[tex]\[ m = \frac{8}{-12} = -\frac{2}{3} \][/tex]

Therefore, the slope of the line passing through points [tex]\( G(3, -1) \)[/tex] and [tex]\( H(-9, 7) \)[/tex] is [tex]\( -\frac{2}{3} \)[/tex] or approximately [tex]\(-0.6667\)[/tex].

To sum up, the slope [tex]\( m \)[/tex] of the line [tex]\( GH \)[/tex] is [tex]\(-\frac{2}{3}\)[/tex] or [tex]\(-0.6667\)[/tex].