Building linear functions for each situation, the inequality is:
[tex]18x + 100 < 15x + 160[/tex]
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Choice A:
Thus, the cost of inviting x guests is given by:
[tex]C_a(x) = 18x + 100[/tex]
Choice B:
Thus, the cost of inviting x guests is given by:
[tex]C_b(x) = 15x + 160[/tex]
A cost less than B, thus, the inequality is:
[tex]C_a(x) < C_b(x)[/tex]
[tex]18x + 100 < 15x + 160[/tex]
A similar problem is given at https://brainly.com/question/13270950