Charlie has a $30 smoothie gift card. each time he uses the card to buy a smoothie 2 dollars is the duct tape from his card, if the balance on his car today is 12 dollars, how many smoothie has she purchase with the card?

The sum of the product of 4 and x and the product of 7 and y is 61. the sum of the product of 12 and x and the product of 21 and y is 61. what are the values of x and y?

The water has been on the stove y=9.5x+62.1 after how many minutes will the tempature be 138.1 f

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.