Chapter 7 Exponential and Logarithmic Functions - 7.7 Write and Apply Exponential and Power Functions - 7.7 Exercises - Mixed Review - Page 536: 55

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Let $t$ be the number of toppings. Let $C$ be the total cost. We have 18 dollars and we are able to buy a pizza that costs 11 dollars plus 2 toppings. Obtain: $11+2t\leq18\\ \Leftrightarrow 2t\leq7\\\Leftrightarrow t\leq\frac{7}{2}\\\Leftrightarrow t\leq3.5$ Hence, we can get 3 toppings or less.