Republic of the Philippines Department of Education Region VII, Central Visayas Division of Cebu Province SELF-LEARNING HOME TASK (SLHT) Subject: Mathematics Grade: 8 Quarter: 2 MELC: illustrates and finds the slope of a line given two-points, equation, and graph Competency Code: M8AL-Ie-5 Objectives: Knowledge : define the slope Skills : solve for the slope of a line using the given two points, equation and graph Values / Attitude: observe accuracy in applying slope in real-life situations Subject Matter : Slope of the line Procedure: A. Readings/Discussions Shown at the right is the picture of Mount Mayon. It is one of the fascinating volcanoes in the Philippines because of its almost symmetrical conical shape. The approximate steepness of the volcano is labelled by the line. The slope of the line can be used to describe how steep Mount Mayon is. A line can be describe by its steepness or slope. The slope m of a line can be computes by finding the qoutient of the rise and the run. That is, 𝑟𝑖𝑠𝑒 𝑟𝑢𝑛 𝑚= slope The rise refers to the vertical change or change in y-coordinate while the run is the horizintal change or change in x-coordinate. 𝑚= 𝑟𝑖𝑠𝑒 𝑣𝑒𝑟𝑡𝑖𝑐𝑎𝑙 𝑐ℎ𝑎𝑛𝑔𝑒 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑦 − 𝑐𝑜𝑜𝑟𝑑𝑖𝑛𝑎𝑡𝑒 = = 𝑟𝑢𝑛 ℎ𝑜𝑟𝑖𝑧𝑜𝑛𝑡𝑎𝑙 𝑐ℎ𝑎𝑛𝑔𝑒 𝑐ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑥 − 𝑐𝑜𝑜𝑟𝑑𝑖𝑛𝑎𝑡𝑒 The slope m of the line passing through two points 𝑃1 (𝑥1 , 𝑦1 ) 𝑎𝑛𝑑 𝑃2 (𝑥2 , 𝑦2 ) is given by 𝑚= 𝑦2 − 𝑦1 𝑦1 − 𝑦2 𝑜𝑟 𝑚 = , 𝑤ℎ𝑒𝑟𝑒 𝑥1 ≠ 𝑥2 𝑥2 − 𝑥1 𝑥1 − 𝑥2 Examples: a. Two-points b. Graphs c. Equation A. Finding the slope in given two-points: Suppose we take two arbitrary points (0,-2) and (3,2). Solution: a. Assign values for (𝑥1 , 𝑦1 ) 𝑎𝑛𝑑 (𝑥2 , 𝑦2 ) (0,-2) and (3, 2). 𝑦2 𝑥1 𝑦1 𝑥2 b. Substitute to the formula c. Compute: 𝑚 4 d. 𝑚 = 3 = 𝑦2 −𝑦1 𝑥2 −𝑥1 = 𝑚= 2−−2 3−0 𝑦2 −𝑦1 𝑥2 −𝑥1 2+2 4 3 3 = = B. Finding the slope in a given graph: The line passes through points (0,1) and (-1, -3). Moving from 𝑃1 𝑡𝑜 𝑃2 , the rise, or the difference between the y-coordinates is -3 – 1 = -4. The run difference between x-coordinates is -1 – 0 = -1. So, the slope is -4/-1 or 4. Note: The slope of a horizontal line is zero, while undefined in vertical line. The value of the slope 𝑚 tells the trend of the graph. If 𝑚 is positive, then the graph is increasing from the left to right. If 𝑚 is negative, then the graph is decreasing from left to right. If 𝑚 is zero, the the graph is a horizontal line. If 𝑚 is undefined, then the graph is a vertical line. C. Finding the slope in a given equation. The figure above shows the graph of the equation 𝒚 = 𝟒𝒙 + 𝟏. Solution: The slope-intercept Form is 𝒚 = 𝒎𝒙 + 𝒃, where 𝑚 is the slope and 𝑏 is the y-intercept. In the given equation the slope is 4. Why? 𝒚 = 𝟒𝒙 + 𝟏 y-interccept Slope (m) B. Exercises/Activities: Find the slope the following given: 1. (1, 2) and (3, 4) 2. (5, 6) and ( 0, 11) 3. 5. 𝒚 = 𝟖𝒙 + 𝟐 6. 𝒚 = −𝟑𝒙 + 𝟓 4. 4. C. Assessment/Application/Outputs (Please refer to DepEd Order No. 31, s. 2020) 1. Find the slope of the line with the equation y = 2x + 4? a. 2 b. -2 c. 4 d. -4 2. How will you solve for the slope of a line given two points? a. solve for the change in y over change in x b. solve for the change in x over a change in y c. solve for the change in y multiplied by the change in x d. solve for the change in x multiplied by the change in y 3. Which of the following equations is the steepest? a. y = 2x + 6 b. y = 4x + 2 c. y = 5x + 1 d. y = 7x + 2 4. Which of the following equations has a slope equal to -10? a. y = -10x + 4 b. y = 3x + 10 c. y = -2x + 4 d. y = 7x + 9 5. What is the slope of the graph shown at the right? a. 0 b. 1 c. 2 d. undefined 6. What is the slope of the line with the points (0, 1) (1, 0)? a. -1 b. 1 c. 2 d. -2 7. What is the graph of a line with a slope equal to 0? a. increasing from left to right b. decreasing from left to right c. horizontal line d. vertical line 8. Which of the following graphs has a negative slope? . 9. Which of the following equations has the slope equal to 3? a. y = 4x + 3 b. y = 3x + 2 c. y = -3x + 5 d. y = x+ 5 10. In the slope-intercept form, y = mx + b, what letter represents the slope of a line? a. m b. y c. b d. x References: DepEd Mathematics Teacher’s Guide 8. pp.162 - 170 DepEd Mathematics Learners Module 8, pp. 182 – 186 DepEd Cebu Province - Mathematics Module 9 Prepared by JENNILYN S. COLLAMAT Teacher 1, Langin National High School Verified by: MA. LOURDES T. CABONILAS Principal 1 GUIDE For the Teacher: You may give other exercises/reinforcement activities other than the ones provided for in this SLHT. For the Learner: Please read carefully the key points/readings and follow correctly directions in accomplishing exercises/tasks. For the Parent/Home Tutor: Kindly guide learner in accomplishing this home task. Should you need assistance, you may contact the subject teacher to address questions or give clarifications/discussions. Republic of the Philippines Department of Education Region VII, Central Visayas Division of Cebu Province SELF-LEARNING HOME TASK (SLHT) Subject: Mathematics Grade: 8 Quarter: 2 MELC: illustrates and finds the slope of a line given two-points, equation, and graph Competency Code: M8AL-Ie-5 Name: ______________________________ Section: ________________________ Answer Sheet (Return this paper only) B. EXERCISES/ACTIVITIES 1. 2. 3. 4. 5. 6. C. ASSESSMENT/APPLICATION/OUTPUTS 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.