SOLUTION: 1)in a polygon there are 6 right angles and the remaining angles are all equal to 200 degree each the number of sides the polygon has ? and . . 2) the ratio between the ra

Algebra ->  Polygons -> SOLUTION: 1)in a polygon there are 6 right angles and the remaining angles are all equal to 200 degree each the number of sides the polygon has ? and . . 2) the ratio between the ra      Log On


   

Question 922005: 1)in a polygon there are 6 right angles and the remaining angles are all equal to 200 degree each the number of sides the polygon has ?
and
.
.
2) the ratio between the radius of the base and the height of the cylinder is 2 :3 if the volume is 1617 cm cube the total surface area of cylinder is ?
Found 2 solutions by stanbon, multiplier:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1)in a polygon there are 6 right angles and the remaining angles are all equal to 200 degree each the number of sides the polygon has ?
Question:: Are you saying there are 6 interior angles?
Comment:: If there are 6 right angles, the sum of the corresponding
exterior angles would be 720. But the sum of the exterior angles
must be 360, if the polygon is convex. All I can say is, you have
a strange polygon.
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and
.
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2) the ratio between the radius of the base and the height of the cylinder is 2 :3 if the volume is 1617 cm cube the total surface area of cylinder is ?
radius = 2x ; height = 3x
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Volume = area of base*height
1617 = (pi*x^2)*3x
1617 = 3pix^3
x^3 = 1617/3pi
x = 5.83
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Surface area = Perimeter*height
radius = 2x = 11.66
diameter = 23.33
SA = (pi*23.33)*(3*5.83) = 407.95pi cm^3
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Cheers,
Stan H.
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Answer by multiplier(8) About Me  (Show Source):
You can put this solution on YOUR website!

let r=radius of the base of the cylinder
h= height of the cylinder
the ratio between the radius of the base and the height is 2:3
this means that if you divide the radius by the height of the cylinder
quotient is 2/3 so: r/h=2/3
solving for h:
h=3r/2 (equation 1)
the volume of the cylinder is 1617 cm cube
v=area of the base multiplied by its height
v=pi*r^2(h) (equation 2)
substitute value of h from (equation 1) in (equation 2)
v=pi*r^2(3r/2)
v= 3/2(pi)r^3
equating v to the given volume which is 1617 cm cube:
3/2(pi)r^3=1617
r^3=1617*2/(3*pi), r^3 = 343, r= 7cm
solving for h in equation 1:
h=3r/2
h= 3*7/2= 10.5 cm
surface area= base perimeter times height
SA= 2*pi*r*h where pi=3.1416
SA= 2*3.1416*7*10.5
SA= 461.82 sq. cm