120º is 1/3 of a complete revolution of 360º. So the area of this sector should be 1/3 the area of the complete circle.
A circle with radius 9 has area 9^2 π = 81π.
So the sector has area 81π/3.
Put another way: The area <em>A</em> of a circular sector and its central angle <em>θ</em> (in degrees) occur in the same ratio as the area of the entire circle with radius <em>r</em> according to
<em>A</em> / <em>θ </em>º = (π <em>r </em>^2) / 360º
==> <em>A</em> = π/360 <em>θ r</em> ^2
In this case, <em>r</em> = 9 and <em>θ</em> = 120º, so
<em>A</em> = π/360 * 120 * 81 = 81π/3
Number of zids=x
number of zods=y
number of zid legs=5x
number of zod legs=7y
so
5x+7y=140
try to get it into slope intercept from so you can graph is (y=mx+b)
5x+7y=140
subtract 5x from both sides
7y=140-5x
divide both sides by 7
y=20-5/7x
y=-5/7x+20
plug in numbers for x and get numbers for y (you can only plug in multiples of 7 for x so that there are a whole number of zids and since you are counting, x and y must never be negative)
lets try 0 for x
y=-5/7(0)+20
y=20
so x=0 and y=20 is an answer (if you can have only one of that species)
lets try 7 for x
y=-5/7(7)+20
y=-5+20
y=15
so x=7 and y=15 is an answer
lets try 14 for x
y=-5/7(14)+20
y=-10+20
y=10
so x=14 and y=10 is another answer
lets try 21 for x
y=-5/7(21)+20
y=-15+20
y=5
so x=21 and y=5 is another answer
lets try 28 for x
y=-5/7(28)-20
y=-20+20
y=0
so x=28 and y=0 is an answer (if there can be only one of a species)
if we go further, then y will be negative so the answers are
(x,y)
(0,20)
(7,15)
(14,10)
(21,5)
(28,0)
if it is allowed that only one species exists then there are 5 possible answers
if both must exist simultaneously, then there are only 3 answers
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Answer:
12.5%
Step-by-step explanation:
8 / 64*100 =
(8 * 100) / 64 =
800 / 64 = 12.5
Hope this helped buddy! :D
The best math that i think you should take would be calculus.