Answer:
AREA:
CIRCUMFERENCE:
Step-by-step explanation:
The formula that is used to calculate the area of a circle is:
Where "r" is the radius of the circle.
The formula for calculate the circumference of a circle is:
Where "r" is the radius of the circle.
Then, you need to find the radius. This is:
Substituting the radius, you get that the area and the circumference are:
AREA:
CIRCUMFERENCE:
Answer:
a = 5
Step-by-step explanation:
If it's easier for you, you can replace n(a) with y and put a as x.
Now the equation is y = 7x + 4.
It asks you to put in 39 as y.
39 = 7x + 4.
To solve this, the goal is to isolate the variable on one side. The first step I see is to subtract the 4 from both sides.
35 = 7x
Now divide both sides by 7 and we're done!
5 = x
Let x be the number of square feet to be mowed
215 square feet take 22 minutes
x square feet take 12 minutes
Answer:
1/10 per sec
Step-by-step explanation:
When he's walked x feet in the eastward direction, the angle Θ that the search light makes has tangent
tanΘ = x/18
Taking the derivative with respect to time
sec²Θ dΘ/dt = 1/18 dx/dt.
He's walking at a rate of 18 ft/sec, so dx/dt = 18.
After 3seconds,
Speed = distance/time
18ft/sec =distance/3secs
x = 18 ft/sec (3 sec)
= 54ft. At this moment
tanΘ = 54/18
= 3
sec²Θ = 1 + tan²Θ
1 + 3² = 1+9
= 10
So at this moment
10 dΘ/dt = (1/18ft) 18 ft/sec = 1
10dΘ/dt = 1
dΘ/dt = 1/10 per sec
