Just keeping going with 16×-2=?×-2=?×-2 untill u get you your ninth nuber as well with tge 2 is a negative, so a a positive × a negative equal a negative and a negative × a negative equal
<span>tan(15) =
sin(15) / cos(15) =
sin(45 - 30) / cos(45 - 30) =
[ sin(45)cos(30) - sin(30)cos(45) ] / [ cos(45)cos(30) + sin(45)sin(30)]
Since sin(45) = cos(45) = √2/2, you can just factor that out from the top and bottom
[ cos(30) - sin(30) ] / [ cos(30) + sin(30)]
[ √3/2 - 1/2 ] / [ √3/2 + 1/2]
(√3 - 1) / (√3 + 1)
(√3 - 1)^2 / (√3+1)(√3 - 1)
(√3 - 1)^2 / (3 - 1)
(3 - 2√3 +1) / 2
2 - √3
There's also a formula for tan(a-b), but I couldn't remember it off hand.</span>
Lets get started :)
The First question:
Diameter = 20 ft
Radius =

of 20 (diameter) = 20 ft
Area formula of a circle is
A =

r²
=

(10)²
=100

ft²
≈ 314 ft²The answer will be the second optionThe Second question:
radius of circle = 12mm divided into 20 sectors area
A =

r²
=

(12)²
= 144

ft²
Divide into 20 equal sector areas =
≈ 22.6 mm²Your answer will be the third optionThe Third Question:
90°, sector area = 36

, Radius = ?



and

cancels out
We can now cross multiply
360 × 36 = 90r²
12960 = 90r²
Divide by 90 on either side

144 = r²
Take squareroot
x = 12 inYour answer will be the third option
Answer:
580m^2
Step-by-step explanation:
600m^2 -20m=580m^2