Sharp EL9900 manual = 2x 5 and y = 7 intersect at 6,7

EL-9900 Graphing Calculator

Step & Key Operation Display Notes

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Move the tracer and find another intersection.

2nd F CALC 2

Solve the inequalities.

y = 2x - 5 and y = 7 intersect at (6,7).

The solution to the “double” inequality -1 ≤ 2x - 5 ≤ 7 con- sists of all values of x in be- tween, and including, 2 and 6 (i.e., x ≥ 2 and x ≤ 6). The so- lution is 2 ≤ x ≤ 6.

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 EL-9900 allows the solution region to be indicated visually using the Shade feature. Also, the points of intersection can be obtained easily.

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