standard_description: Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
problem_activity: Use the coordinate plane below for Parts (a) and (b).
[IMG]
a.   Draw a line through points
M
and
N
.
b.   Draw a second line that is perpendicular to
$$\overleftrightarrow{MN}$$
.


aligns: no