Answer:
x=101/65, y=-16/65. (101/65, -16/65).
Step-by-step explanation:
4x+9y=4
9x+4y=13
----------------
9(4x+9y)=9(4)
-4(9x+4y)=-4(13)
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36x+81y=36
-36x-16y=-52
----------------------
65y=-16
y=-16/65
4x+9(-16/65)=4
4x-144/65=4
4x=4+144/65
4x=404/65
x=(404/65)/4=101/65
x=101/65, y=-16/65.
Well, I know to find the mean you add all the numbers and divide it by how many numbers there were, so I'm guessing you just do that with the stem and leaf plot. I hoped this helped a bit
V=(1/3)hpir^2
lets say this is original, undoubled volume
so o=v=(1/3)hpir^2
so for new volume, or n, that is r to 2r, doubled radius
n=(1/3)hpi(2r)^2
n=(1/3)hpi4r^2
n=4((1/3)hpir^2)
remmember that o=(1/3)hpir^2
n=4(o)
it is 4 times the old one