Answer:
see explanation
Step-by-step explanation:
Given
4
- 5a² + 1 = 0
Use the substitution u = a², then equation is
4u² - 5u + 1 = 0
Consider the product of the coefficient of the u² term and the constant term
product = 4 × 1 = 4 and sum = - 5
The factors are - 4 and - 1
Use these factors to split the u- term
4u² - 4u - u + 1 = 0 ( factor the first/second and third/fourth terms )
4u(u - 1) - 1(u - 1) = 0 ← factor out (u - 1) from each term
(u - 1)(4u - 1) = 0
Equate each factor to zero and solve for u
u - 1 = 0 ⇒ u = 1
4u - 1 = 0 ⇒ 4u = 1 ⇒ u = 
Convert u back into terms of a, that is
a² = 1 ⇒ a = ± 1
a² = ⇒ a = ± 
Solutions are a = ± 1 , a = ±
Answer:
144°
Step-by-step explanation:
step 1
Find the measure of the central angle of the regular pentagon
Divide 360 degrees by 5 (the number of sides)
Let
c----> the center of the pentagon
we know that
m∠ECA=72°
m∠ACB=72°
therefore
m∠ECB=m∠ECA+m∠ACB
substitute the values
m∠ECB=72°+72°=144°
The measure of angle ECB is equal to the degrees that the pentagon rotate
The volume of sphere is 
feet cubed.
Step-by-step explanation:
Given,
Surface area of sphere = 196π square feet
Surface area of sphere = 4πr²
We will find radius of sphere.
Dividing both sides by 4π
Taking square root on both sides
The radius is 7 feet.
Volume of sphere = 
The volume of sphere is feet cubed.
Keywords: volume, surface area
Learn more about surface area at:
#LearnwithBrainly
<span>No.
To check this yourself, you need the denominators to be the same to be able to easily compare the two.
For example, does 5/8 = 40/64?
1. Determine what you would need to do to the denominator in 5/8 to make it 64. (Multiply it by 8)
2. Find what fraction is equal to 1 with a denominator of 8. (8/8)
3. Multiply the fraction 5/8 by the one you just found (8/8), numerator times numerator, denominator times denominator.
4. Compare the answer with the second fraction.
It is important that when you multiply the denominator by any number you multiply the numerator by the same number. This is to preserve the fraction's value. This works because any number divided by itself is equal to 1, AND when you multiply any number by 1 (whether 1 is in the form of 1 or 4/4 or 8/8 or 234/234), the answer is always equal to the original number.
Another way to check would be to simply enter 1/2 into a calculator, write down the answer. Next enter 5/8 into a calculator. If the answers are the same, they are equal.</span><span>
</span>
ANSWER: The statistical procedure that should be performed is REGRESSION.
Step-by-step explanation: Regression is a statistical procedure that is used to estimate the relationship between an independent variable and a dependent variable using their mean values.
The independent variable in this case is the hours each student spend in studying, while the dependent variable is the students grade.
Since the researcher wants to determine if the hours a student spend in studying maths and science has any significant effect on their grades. The researcher should use regression, because it will show if the two variables are related and how it relates, by showing how far the points are from the trend lines of the graph.
