standard_description: Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles. For example, arrange three copies of the same triangle so that the sum of the three angles appears to form a line, and give an argument in terms of transversals why this is so.
problem_activity: Problem 1
Graph the system of equations in the coordinate plane and identify the solution.
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Problem 2
Graph the system of equations in the coordinate plane. Identify the solution to the system and verify it algebraically.
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Problem 3
Line
$$a$$
is shown on the coordinate grid. Construct line
$$b$$
on the coordinate grid so that
Line
$$a$$
and line
$$b$$
represent a system of linear equations with a solution of (
$$6$$
,
$$-2$$
).
The slope of line
$$b$$
is greater than
$$-1$$
and less than
$$0$$
.
The
$$y$$
-intercept of line
$$b$$
is positive.
[IMG]


aligns: no