Plans and Worksheets for Grade 8
Plans and Worksheets for all Grades
Lessons for Grade 8
Common Core For Grade 8
Examples, solutions, worksheets, and videos to help Grade 8 students learn some facts about graphs of linear equations in two variables.
New York State Common Core Math Grade 8, Module 4, Lesson 21
Download Worksheets for Grade 8, Module 4, Lesson 21
Lesson 21 Student Outcomes
• Students write the equation of a line given two points or the slope and a point on the line.
• Students know the traditional forms of the slope formula and slope-intercept equation.
Lesson 21 Student Summary
The point-slope form of a linear equation is given by m(x2
) = y2
Given a known (x, y), then the equation is written as m(x - x1
) = y - y1
The following is slope-intercept form of a line: y = mx + b
In this equation, m is slope and b is the y-intercept.
To write the equation of a line you must have two points, one point and slope, or a graph of the line.
Lesson 21 Opening Exercise
Examples 1 - 4
Let a line l be given in the coordinate plane. What linear equation is the graph of line?
1. Write the equation for the line l shown in the graph.
2. Write the equation for the line l shown in the graph.
3. Determine the equation of the line that goes through points (-4, 5) and (2, 3).
4. Write the equation for the line l shown in the graph.
5. A line goes through the point (8, 3) and has slope m = 4. Write the equation that represents the line.
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