Selena is planning a birthday party for her little sister at a local zoo. The price depends on the number of children that attend the party. The price per child is normally $5. However, if there are more than 12 children in a group, the group can pay an $18 fee plus $2 per child. Which piecewise-defined function best models the cost of the party c(x) if Selena invites x children?

geometry: triangles

solvers

lessons

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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

the answer is 99.

a.for lorena 14 hours makes $126   for 16 hours she makes 144

for julie 6 hours makes $72 for 21 hours its $252

b. julie makes more money than lorena julie makes $12 an hour and lorena makes $9  

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