r
sin
θ
=
−
3
Explanation:
Imagine we have a point
P
with Rectangular (also called Cartesian) coordinates
(
x
,
y
)
and Polar coordinates
(
r
,
θ
)
.
The following diagram will help us visualise the situation better:
https://keisan.casio.com/exec/system/1223526375
https://keisan.casio.com/exec/system/1223526375
We can see that a right triangle is formed with sides
x
,
y
and
r
, as well as an angle
θ
.
We have to find the relation between the Cartesian and Polar coordinates, respectively.
By Pythagora's theorem, we get the result
r
2
=
x
2
+
y
2
The only properties we can say about
θ
are its trigonometric functions:
sin
θ
=
y
/
r
⇒
y
=
r
sin
θ
cos
θ
=
x
/
r
⇒
x
=
r
cos
θ
So we have the following relations:
⎧
⎪
⎨
⎪
⎩
r
2
=
x
2
+
y
2
y
=
r
sin
θ
x
=
r
cos
θ
Now, we can see that saying
y
=
−
3
in the Rectangular system is equivalent to say
r
sin
θ
=
−
3
Answer link
Jim G.
May 19, 2018
r
=
−
3
sin
θ
Explanation:
to convert from
cartesian to polar
∙
x
x
=
r
cos
θ
and
y
=
r
sin
θ
⇒
r
sin
θ
=
−
3
⇒
r
=
−
3
sin
θ
Answer:
The balance after four years is $1129.27
Step-by-step explanation:
The formula for compound interest, including principal sum, is 
- A = the future value of the investment/loan, including interest
- P = the principal investment amount (the initial deposit or loan amount)
- r = the annual interest rate (decimal)
- n = the number of times that interest is compounded per unit t
- t = the time the money is invested or borrowed for
∵ $800 is deposited in an account
∴ P = 800
∵ The account pays 9% annual interest
∴ r = 9% = 9 ÷ 100 = 0.09
∵ The interest is compounded annually
∴ n = 1
∵ The time is 4 years
∴ t = 4
- Substitute the values of P, r, n, and t in the formula above
∵ 
∴ 
∴ A = 1129.265
∴ The balance after four years is $1129.27
The length of a median is equal to half the square root of the difference of twice the sum of the squares of the two sides of the triangle that include the vertex the mediam is drawn from and the square of the side of the triangle the median is drawn to.
triangle sides by a, b, c.
ma=122c2+2b2−a2
mb=122c2+2a2−b2
mc=122a2+2b2−c2
Depending on how big the center is, I would say 15.
I hope this helped!
Since the number of days in July and in August is the same, there is no need to work out on the total number per month.
The mean number of people per day in August = 160 + 20 = 180
Answer: 180
