Title: Investigating the Relationship Between Coordinate Grids and Equations of Straight Lines

Subject: Mathematics Grade Level: MYP 4 (Grade 9) Criteria: A (Knowing and Understanding) and D (Applying Mathematics in Real-World Contexts)

Task Description: In this task, you will explore the relationship between coordinate grids and equations of straight lines. You will demonstrate your understanding of the concepts by applying them to real-world scenarios.

Criteria A: Knowing and Understanding 1. Define the key terms related to coordinate grids and equations of straight lines, such as x-axis, y-axis, origin, slope, y-intercept, and equation of a straight line. 2. Explain the concept of slope and how it relates to the steepness of a line. 3. Describe the process of finding the equation of a straight line given two points on the line.

Criteria D: Applying Mathematics in Real-World Contexts 1. Choose a real-world scenario that can be represented by a straight line on a coordinate grid. For example, the relationship between the number of hours studied and the test score achieved. 2. Create a coordinate grid and plot at least five points that represent the data from your chosen scenario. 3. Calculate the slope of the line that passes through two of the plotted points. 4. Write the equation of the straight line using the slope-intercept form (y = mx + b), where m represents the slope and b represents the y-intercept. 5. Interpret the equation of the line in the context of your chosen scenario. For example, explain what the slope and y-intercept represent in terms of the relationship between hours studied and test scores. 6. Use the equation of the line to make predictions or solve problems related to your chosen scenario. For instance, predict the test score if a student studies for 10 hours.

Assessment: Your performance will be assessed based on your ability to: - Accurately define key terms related to coordinate grids and equations of straight lines. - Demonstrate a clear understanding of the concept of slope and its relationship to the steepness of a line. - Explain the process of finding the equation of a straight line given two points on the line. - Choose an appropriate real-world scenario and represent it on a coordinate grid. - Accurately calculate the slope of the line passing through two points. - Write the equation of the straight line using the slope-intercept form. - Interpret the equation of the line in the context of the chosen scenario. - Use the equation of the line to make predictions or solve problems related to the chosen scenario.

Note: You may use graphing software or graph paper to complete this task.