<h3>Problem Solution</h3>
Assuming the spool is a cylinder and the circumference we're winding around is that of a circle with the given area, we can write the relation between circumference and area as
... C = 2√(πA)
10 times the circumference is then
... 10C = 20√(π·20 cm²) = 40√(5π) cm ≈ 159 cm
<h3>Formula Derivation</h3>
The usual formulas for circumference and area are
... C = 2πr
... A = πr²
If we multiply the area formula by π and take the square root, we get
... πA = (πr)²
... √(πA) = πr
Multiplying this by 2 gives circumference.
... C = 2√(πA) = 2πr
B would be at 4 since b+5 = 9
subtract 5 from both sides
b = 4
Answer:
b = 10
Step-by-step explanation:
P = 2 (l + b)
l = 15
P = 50
Substitute
50 = 2 (15 + b)
multiply
50 = 30 + 2b
subtract
20 = 2b
divide
b = 10
Answer: 
Step-by-step explanation:
1. As you can see,
is equal to the other quadratic equation
.
2. Then, this would the same as write the quadratic equations as following:


3. And then set them equal to each other, as you can see below:

Substituting, you obtain:

3. Keeping the above on mind, you can set up the given equations as a system of equations as folllowing:
