8th Grade Math Linear Relationships and Functions

Important points of the linear relationship

The equation can have up to two variables, but it cannot have more than two variables.

All the variables in the equation are to the first power. None are squared or cubed or taken to any power. And also, none of the variables will be in the denominator.

The equation must be graphed as a straight line. Linear relationships such as y = 2 and y = x all graph out as straight lines. When graphing y = 2, you get a line going horizontally at the 2 mark on the y-axis. When graphing y = x, you get a diagonal line crossing the origin.

The expression for the linear equation is; y = mx + c

Linear relationship Example

1.    Let’s draw a graph for the following function:

F(2) = -4 and f(5) = -3

·       Let’s rewrite it as ordered pairs(two of them).

·       f(2) =-4 and f(5) = -3

·       (2, -4) (5, -3)

2.    Find the slope of a graph for the following function.

f(3) = -1 and f(-8) = -6

·       Let’s write it again as ordered pairs

·       f(3) =-1 and f(8) = -6

·       (3, -1) (8, -6)

·       we will use the slope formula to evaluate the slope

·       (3, -1) (8, -6)

·       (x₁ , y₁) (x₂ , y₂)

·       Slope Formula, m =y2−y1/x2−x1

·       −6−(−1)8−(−3)=−55

·       m = 1 is the slope for this function.  

Teachers are looking for lessons, activities, worksheets, quiz, mock test papers that are suitable for 8th grade math. Here's your compilation of lessons suitable for 8th grade to share with your students.

Sum Up

Linear relationships can give insight into how variables interact with one another. Linear relationships can support statistical analysis to determine the presence of correlations and causal relationships between variables.