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Math
A |
Graphing
an Inequality |
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If
you can graph a straight line, you can graph an
inequality!
After
graphing the line, there
are only two additional steps to remember.
(1) Choose a point not on the line and see if
it makes the inequality true. If the inequality is
true, you will shade THAT side of the line -- thus shading
OVER the point. If it is false, you will shade the
OTHER side of the line -- not shading OVER the point.
(2) If the inequality is LESS THAN OR
EQUAL TO or GREATER THAN OR EQUAL TO, the line is drawn as
a solid line. If the inequality is simply LESS THAN
or GREATER THAN, the line is drawn as a dashed line. |
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Graphing
an Inequality |
1. Solve the equation
for y (if necessary).
2. Graph the equation as if it contained an = sign.
3. Draw the line solid if the inequality is 
or 
4. Draw the line dashed if the inequality is <
or >
5. Pick a point not on the
line to use as a test point.
The point (0,0) is a good test
point if it is not on
the line.
6. If the point makes the inequality true, shade
that
side of the line. If the point does not make
the
inequality true, shade the opposite side of the line. |
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Graph the
following inequality
y
3x - 1
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Graph the inequality
y
3x - 1
The point
(-2,1) was chosen as the test point, because it can be clearly
seen in the diagram.
[The easiest test point is usually (0,0)]
1
3(-2) - 1
1 -6
-1
1 -7
false
(shade the
opposite side of the line) |
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