Answer:

Step-by-step explanation:

Im going to assume that 3√ is √3
And √3 is irrational because You cant square root it without getting nuked with a Random Number generator of decimals.
If you have never used a unit circle, I recommend making one.
R for the following degrees are
30*= 4((3^1/2)/2)^2
60*= 8(2^1/2)(2^1/2)^2
90*= (8((3^1/2)/2))/4
The volume of the cone is approximately 8.2 inches cubed
So
a^2+b^2=c^2
c=hypotenuse
a^2+b^2=20^2=400
if the permiter is 42 then
p=hypotonuse+side+side
42=20+side+side
subtract 20 from both sides
22=side+side
a+b=22
subtract b from both sides
a=22-b
subsitute for a in equation below
a+2+b^2=c^2
(22-b)^2+b^2=400
b^2-44x+484+b^2=400
2b^2-44x+484=400
divide both sides by 2
b^2-22x+242=200
subtract 200 from both sides
b^2-22x+42=0
factor
(b+/-number)(b+/-number)
to find the numbers, find which 2 number multiply to 42 and add to get -22
the numbers must be neative since same signs multiplied=positive and negative+negative=negative
(b-number)(b-number)
facrors of 42=2,3,6,7,14,21
2,21
3,14
6,7
it's hard to find the number, but the numbers are -19.8882 and -2.11181
(b-19.8882)(b-2.11181)=0
if xy=0 then assume that x and y=0
b-19.8882=0
add 19.8882 to both sides
b=19.8882
b-2.11181=0
add 2.11181 to both sides
b=2.11181
the side legnths are 19.8882 units and 2.11181 units