Grade 8 Task
Given two points that represent buildings, write and graph an equation to represent 1st Street.
Then given one point of another building on a parallel street, determine if there is enough
information to graph the 2nd Street. If so, graph and write its equation.
Solution(s)/Strategies
1. Students might figure out on their own that the 2ndStreet has to have the same slope in order to be parallel and
use the rise/run to graph the street, and then write the equation of their graph.
2. Students might sketch a parallel line and draw the conclusion that the slopes are the same and then estimate
the equation that represents the 2nd Street.
3. If a student knows the slopes are the same, they might use the slope and the point of the building on 2nd street
to write the equation and then graph it.
 1.2.1 The student will determine the equation for a line, solve linear
Content Standard(s)

What mathematical concept/idea is
this task going to develop/enforce?
Standards for Mathematical Practice
Describe the classroom structure for
the task (groups, pairs, management
norms, etc.)
What facilitating questions will you
ask students when they need help?
Be specific.
What evidence of student thinking is
demonstrated through completion of
this task?
How will solution(s) be
shared/assessed?
What resources will be needed to
complete the task?
Could this task be extended? If so,
how?
Where did this task originate?
equations, and/or describe the solutions using numbers, symbols, and/or
graphs.
1.2.3 The student will solve and describe using numbers, symbols, and/or
graphs if and where two straight lines intersect. (Systems of linear functions
will include coincident, parallel, or intersecting lines.)
The graphs of parallel lines have the same slope.
The equations of parallel lines have the same slope.
Given one point of a line and the slope, you can write an equation of the
line and/or graph the line.
1. Make sense of problems and persevere in solving them.
2. Reason abstractly and quantitatively.
4. Model with mathematics.
7. Look for and make use of structure.
Begin individually and move to partnering with another student so that
they can compare their graphs and responses.
1. What are you being asked to find out?
2. What must you know in order to graph a line?
3. What are the four parts of an equation written in y = mx + b form.
4. What do you know about 2nd street for sure?
5. What have you tried?
Students should be able to describe the relationship between the graphs
of both streets.
Students should be able to graph both streets as parallel lines.
Students should be able to compare the equations of both streets and
conclude that parallel lines have the same slope.
Different approaches to the task can be shared under the document
camera.
Paper, pencil, graph paper, ruler,
Have students write equations for other parallel streets.
Have students graph and write equations for Intersecting/perpendicular
streets.
Chapter 5 Resource book.
Submitted by: Barbara J. Robinson