<span>Point B has coordinates (3,-4) and lies on the circle. Draw the perpendiculars from point B to the x-axis and y-axis. Denote the points of intersection with x-axis A and with y-axis C. Consider the right triangle ABO (O is the origin), by tha conditions data: AB=4 and AO=3, then by Pythagorean theorem:
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{Note, that BO is a radius of circle and it wasn't necessarily to use Pythagorean theorem to find BO}
<span>The sine of the angle BOA is</span>

Since point B is placed in the IV quadrant, the sine of the angle that is <span> drawn in a standard position with its terminal ray will be </span>
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Answer:
25 : 1
Step-by-step explanation:
The diameter of the football is 5 times the diameter of the cricket ball. This means that the radius of the football is also 5 times the radius of the cricket ball.
Let the radius of the football be R.
Let the radius of the cricket ball be r.
This implies that:
R = 5r
Both balls are spherical.
The surface area of the cricket ball is given as:

The surface area of the football is given as:


Therefore, the ratio of their surface areas is:
A : a

= 100 : 4
25 : 1
Answer: E. The population decreased by 11% each year.
Step-by-step explanation: In A, the pollution increases at a constant rate, but in a linear way, in other words in each day, the pollution increases 10 grams; The same goes for C: ice "grows" a few milimeters each day; In D, as volume is calculated by the multiplication of π and its radius, the increase in the volume is still linear. In B, the proportionality is related to the power of the turbine not the growth or decay of it. In E, a population grows or decreases in a form of A=A₀(1±r)^t. In this case: A = A₀ (1-0.11)^t.
In conclusion, the function that better describes an exponential growth or decay is the decrease of a population.
Answer:
Step-by-step explanation:
erasers=e
pencils=p
3e+5p=7.55 ...(1)
6e+12p=17.40
divide by 2
3e+6p=8.70 ...(2)
(2)-(1) gives
p=8.70-7.55=1.15
from (1)
3e+5(1.15)=7.55
3e+5.75=7.55
3e=7.55-5.75
3e=1.80
e=1.80/3=0.60
cost of 1 eraser=$0.60
cost of 1 pencil =$1.15