System of Two-Variable Inequalities
The solution region of a system of
Example
Solve a system of
x 2 + y ≤ 1
Before There may be differences in the results of calculations and graph plotting depending on the setting. Starting Return all settings to the default value and delete all data.
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1 Rewrite each inequality in the system |
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| 2x + y ≥ | 1 ➞ y ≥ | 1 - 2x | |||||
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| x 2 + y ≤ | 1 ➞ y ≤ | 1 - x 2 |
2Enter y = 1 - 2x for Y1 and y = 1 - x 2 for Y2.
Y= 1
1 —
— 2 X//T/n
X//T/n x2
ENTER
3Access the set shade screen
2nd F DRAW G
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4Shade the points of y
2nd F VARS A ENTER A 1
2nd F VARS ENTER 2
5Graph the system and find the intersections.
GRAPH
2nd F CALC 2 2nd F CALC 2
6Solve the system.
The intersections are (0, 1) and (2,
The solution is 0 ≤ x ≤ 2.
Graphical solution methods not only offer instructive visualization of the solution process, but they can be applied to inequalities that are often difficult to solve algebraically. The