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Interpreting Slope and Intercept

8.SP.A.3
Answer Keys Here

Aligned To Common Core Standard:

Grade 8 Statistics & Probability - 8.SP.A.3

How to find the Slope and Intercept of a line? When we are learning concepts in the co-ordinate geometry, the slope and y-intercept hold are the first ones that we come across. These are the two most important elements of a graphical line. Slope - The slope is the measure of the steepness of a line. It is the ratio that is determined as rise over run. Two parallel lines have the same slope, and the slope of two perpendicular lines are negative reciprocals of each other. Y-intercept - The y-intercept is the point at which the line cuts the vertical or y-axis. An equation of a straight line is; y=mx+c Here, "m" is the slope, and "c" is the y-intercept. Method 1: Using the Graph You can use the graph to calculate the slope and y-intercept. Take two pairs of co-ordinates to calculate the slope. The formula to calculate slope is; m=(y_2-y_1)/(x_2-x_1 ) Simply substituting the coordinates in the formula will help you calculate the slope of the line. For y-intercept, you analyze the graph and see where the graph cuts the y-axis. Method 2: Using the Equation When you use the formula to calculate the slope, you can then use the equation of the straight line to calculate the y-intercept. You substitute the value of m by the slope you calculate, choose a pair of coordinates on the line and substitute the variables x and y with the coordinates. It will help you calculate the y-intercept. Students quickly learn with these worksheets and lessons on how to use slope and y-intercept data to better understand data sets and linear equations.

Printable Worksheets And Lessons






Homework Sheets

Making scatter grams, graphing functions, and calculating slope.

  • Homework 1 - The table below displays the data of apples eaten by Travis in a week. Make a scatter gram of this data.
  • Homework 2 - We make up values for x and in the process we calculate the value of y.
  • Homework 3 - We find that two points on the line are (4,6) and (2, 2). Now we will put the points in slope formula.



Practice Worksheets

Time to create your own data charts from collected data.

  • Practice 1 - The table below displays the upcoming results of class 8th. It displays the number of students in each group.
  • Practice 2 - Make graph using this function: y = x + 8
  • Practice 3 - Calculate the slope of the graph.



Math Skill Quizzes

A similar set of skills is tested here. The scatter grams are fun and helpful.

  • Quiz 1 - We are given the inventory data of a cell phone shop. You have to make a scatter plot according to the data of the cell phones and cell phone boxes.
  • Quiz 2 - Determine the slope of the line that passes through the points - (-11,6), (5,-5)
  • Quiz 3 - Find the slope of any graph on this section.