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Algebra/Dashed Boundary Lines

Question
I am taking algebra 1 and I saw the phrase dashed boundary lines. May you please tell me the definition of this phrase?

Hello Nayla,

I am guessing that came up when graphing linear inequalities, yes?

For example, graphing y>x+1...since it is a strict inequality (i.e. it is
a "greater than" not "greater than or equal to") we graph the line as a dotted
or dashed line to indicate that it is a boundary but we cannot use points on the
line.  If it were a "greater than or equal to" then we graph a solid line to
indicate that we can use points on the line.  See now?

Here is a link that demonstrates the ideas:
http://www.mathsisfun.com/algebra/graphing-linear-inequalities.html

I hope this helps!

Abe

Algebra

Volunteer

Abe Mantell

Expertise

Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!

Experience

Over 15 years teaching at the college level.

Organizations
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.

Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook