Not so sure about the second one, but the first one is pretty simple:
The area of a circle = pi x radius^2
Since you need to find the area of the entire dvd, I'm assuming they mean if the hole in the center wasn't there, so add that to the diameter.
12+1.5 = 13.5
Half of the diameter is the radius, so half of 13.5 = 6.75
Now, multiply pi (3.14) by the radius, but have the radius squared. You'd write the equation like this:
3.14 x 6.75^2 (or on paper, the ^2 would be a small two diagonal from the 5)
Actual answer: 143.06625
You can round that to 143.
If x = # of quarters, then, the # of dimes will be equal to 2x. The total value (z) would be equal to:
z = 0.25x + 0.10(2x)
Then, since you switch the quarters and the dimes, and you have a new total, the resulting equation will be:
1.2 + z = 0.25(2x) + 0.10(x)
Plug in the values you know:
1.2 + (0.25x + 0.10(2x)) = 0.25(2x) + 0.10(x)
Solve for x:
1.2 + (0.25x + 0.20x) = 0.50x + 0.10x
1.2 + 0.45x = 0.60x
1.2 = 0.15x
x = 1.2/0.15 = 8
This means that there are 8 Quarters in her bag right now. So, the amount of dimes is just 2x which is 16. So your answer will be:
She has 8 Quarters and 16 Dimes in her bag right now. Or, $3.60.
If this doesn't make sense, then tell me. I have some resources where I got the answer from to put it into simplest terms. I have the website if you want.
Answer:
23.31 ft
Step-by-step explanation:
Reference angle = 47°
Opp = 25 ft
Adj = x
Apply trigonometry ratio TOA:
Tan 47 = Opp/Adj
Tan 47 = 25/x
x*Tan 47 = 25
x = 25/Tan 47
x = 23.3128772 ≈ 23.31 ft (to 2 d.p)
Answer:
I BELIEVE ITS C
Step-by-step explanation:
Given:
64 total students
x = drama club students
y = yearbook club students
x = y + 10
y = 64 - x
y = 64 - x
y = 64 - (y + 10)
y = 64 - y - 10
y + y = 64 - 10
2y = 54
2y/2 = 54/2
y = 27
x = y + 10
x = 27 + 10
x = 37
To check:
x + y = 64
37 + 27 = 64
64 = 64
