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anonymous
 5 years ago
Multiple choice: Can someone please please help me with some more surface area of pyramids and cones???
anonymous
 5 years ago
Multiple choice: Can someone please please help me with some more surface area of pyramids and cones???

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0do you know the formula for finding out the surface area of a cone?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if not, it is \[\pi (radius)^{2} + (\pi *radius* hypotenuse)\] In the given figure, the radius is denoted by r and the height of the cone is denoted by y. so, by pythogarus's theorem, the hypotenuse, denoted by x is \[\sqrt{r ^{2}+y ^{2}}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0all you need to do now is substitute the values of the radius and hypotenuse in the formula and you will have your answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i think its c, but i want a second opinion

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0i did it but i lost the paper

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so, 138.23m^2 is the surface area. substituting in the formula, we get, \[138.23 = \pi*2^{2}+\pi*2*\sqrt{2^{2}+y ^{2}}\] solve for y. x will be \[\sqrt{2^{2}+y ^{2}}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0\[138.23=12.56+6.28\times \sqrt{2^{2}+ y ^{2}}\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0how would i solve for y

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0138.23=12.56+6.26(sqrt(4+y^2)) therefore 138.2312.56 = 6.28(sqrt(4+y^2)) therefore (138.2312.56)/6.28 = sqrt(4+y^2) therefore 4+y^2 = ((138.2312.56)/6.28)^2 therefore y^2 = (((138.2312.56)/6.28)^2)  4 therefore y = sqrt((((138.2312.56)/6.28)^2)  4)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nvm i thought we were solving for x

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you need to know the value of y to solve for x.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0because x = sqrt(r^2+y^2)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0y = sqrt((((138.2312.56)/6.28)^2)  4).. doing this i got 11.03

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0lets take this one step at a time: 138.2312.56 = 125.67 125.67/6.28 = 20.011 20.011^2 = 400.44 400.444 = 396.44 y = sqrt(396.44)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0right, substituting x = sqrt(19.9^2+2^2) = sqrt(400.44) = 20.011 approximately

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you are welcome. It is really easy once you know the formula. it is all a matter of substituting the correct values.
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