The student council at Hillsdale High School is making T-shirts to sell for a fundraiser, at a price of $ 10 each. The costs, meanwhile, are $ 9 per shirt, plus a one-time setup fee of $ 79 . Selling a certain number of shirts will allow the student council to cover their costs. What will the costs be? How many shirts must be sold?

More than 79 Shirts must be sold.

Step-by-step explanation:

1) Set amount of shirts sold = x

2) Form equation to solve for x, where x > 0

10x - 9x - 79 = 0

Simplify:

1x - 79 = 0

1x = 79

x = 79

Plug this value for x back into the original equation.

10(79) - 9(79) - 79 = 0

790 - ( 790) = 0

In order to break even, the school must sell 79 shirts. If the school sells more than 79 shirts, they will begin to make a profit.

geometry: triangles

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answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584