Question #70266

1 Answer
Oct 11, 2017

Representing Ben's score on the x axis and Jim's score on the y axis, the set of all possible scores for Ben and Jim is:

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Explanation:

Let's call Ben's score #b# and Jim's score #j#. We know 3 things:

#b ge 78#
#g ge 78#
#b + g le 168#

This gives us a system of inequalities with two variables. This means that the best way to represent our solution set is on a coordinate plane.

Let's put Ben's score on the x-axis. We know his score must not be less than 78, so that gives us this inequality:

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Let's also put Jim's score on the y-axis. We know his score must also not be less than 78, so that gives us this inequality;

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Finally, we know that their combined score cannot be greater than 168, which we can represent on this graph by the inequality #x + y le 168#

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If we put all three of these inequalities on the graph at the same time, we see that there is a small area of overlap between them.

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This area of overlap is our solution set. Representing Ben's score with #x# and Jim's with #y#, this area gives all possible pairs of scores for Ben and Jim.

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Final Answer