The value of x and its corresponding value of y represents an ordered pair.
Slope: 12 Interpretation: The length of hair that will grow per month. Months: 8
Practice makes perfect
We are given a table that shows the lengths y in inches of our hair x months after our last haircut.
x
y
1
0.5
2
1
3
1.5
4
2
These points lie on a line. The value of x and its corresponding value of y represents an ordered pair that can be plotted in a coordinate plane. Let's plot the ordered pairs and draw a line through the points.
Now, recall the formula for the slope.
m = y_2-y_1/x_2-x_1
We can find the slope of the line. We will start by substituting x_1= 2, y_1= 1, x_2= 4, and y_2= 2 into the above formula to calculate the slope for the blue line. Let's do it!
The slope of the line is equal to 12. This means that our hair grows one half inch each month. Our hair will grow in inches an amount equal to half of the number of months, which means that it will grow 4 inches in 8 months.
Extra
Linear Equations
A linear equation is an equation whose graph is a line.
This type of equation contains at least one linear term and any number of constants. Let's see a few examples!
& y=2x+1,
& 3x=6 +3,
& 2y+x=4
For those of you who are interested in learning more about the different types of linear equations and their graphs, you can read more about them on the following pages.
