i will try and post the question and tell you how far i got and hopefully some nice guy/girl out there will show me what i did wrong and help me solve the problems before the test tomorrow(adsbygoogle = window.adsbygoogle || []).push({});

1-The heat experienced by a hiker at a campfire is proportional to the amount of wood on the fire, and inversely proportional to the cube of his distance from the fire. If he is 15 feet from the fire, and someone triples the amount of wood burning, how far from the fire would he have to be so that he feels the same heat as before?

okay here is what i did

hiker = k*wood/distance^3

hiker = k(3*wood)/distance^3

but now i'm stuck i feel like i'm missing something that is very important to solve this problem and i don't know what it is..

2-F(x) is given asf(x)=x^(1/5) , and the indicated transformations are applied to its

graph in the given order. Write the equation for the final transformed graph.

a) shift upward 6 units and to the left 7 units

(x^(1/5) +7) +6

b) shift right 4 units, shrink horizontally by a factor of 1/5 and shift downward 2 units

(5x^(1/5) -4)-2

c) reflect over the y-axis, stretch vertically by a factor of 3 and shift upward 1 unit

3(-x^(1/5))+1

d) reflect over the x-axis, stretch horizontally by a factor of 5 and shift left 7 units

-(5x^(1/5)+7)

i gave the equation for all 4 questions but i don't know if all are correct so please help

9. An open box with a square base is to have a volume of 19 ft^3. Find a function that models the surface area, A(x), of the box, where x is the length of the base. Find the box dimensions that minimize the amount of material used to make the box. Round your dimensions to the nearest hundredth.

not only do i not know how to start this well i dont:surprised

thank you in advance

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# Homework Help: Afew precalc problems which i'm having problems with

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