# math

posted by
**Jo**
.

Please help! :)

Garden measures 30x20

Border has a width of x

(I've already solved the first part of my problem, in that the width is 3)

Border needs to be covered to a depth of 3 inches. Pine bark costs $29 per cubic yard. What will the material cost to lay the pine bark border? (Need whole number of yards, not a fraction)

Part two is that we can buy as much or as little as necessary for the border (so a fraction of the cubic yard I want). Write an expression for the cost in $ as a function of the width x, of the border in feet. (Again, depth of 3 inches, cost of $29 per cubic yard).

I then use the function from above in my graphing calculator and need to fill in a table I was given. As a way to double-check that my above function is correct, my instructor has filled in 3 (the width of the border in feet) with the amount of $90.22.

Can anyone help me figure out the function? I've tried everything, and so far I cannot come up with the right answer.

Thank you in advance!