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7. if the value of x varies directly with the value of y, and x = 3 when y = 21. what is the valu y, and x = 3 when y = 21. what is the value of x when y = 105?

The revenue each season from tickets at the theme park is represented by t(c)=5x. the cost to pay the employees each season is represented by r(x)=(1.5)^x. examine the graph of the combined function for total profit and estimate the profit after four seasons

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827