Boundary line — Algebra I · Grade 9 or accelerated Grade 8, what it means and where it is taught
The line you would get by replacing the inequality sign with =.
Taught in Algebra I · Grade 9 or accelerated Grade 8.
Where it is taught
What it rests on
Work through these first if this one does not settle.
- Inequality — A statement that one expression is less than or greater than another.
Practise this idea
2 questions in the course bank use Boundary line, in Systems of Equations & Inequalities.
Problem 1
For y > 2x + 1, is the boundary line solid or dashed?
Worked answer
dashed
> does not include equality
So the line is dashed
Problem 2
A system of two linear inequalities has a solution region shaped like a wedge. This means
- the two boundary lines cross
- the lines are parallel
- there is no solution
- the lines are the same
Worked answer
the two boundary lines cross
Crossing lines cut the plane into four wedges
The solution is one of them