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3 years ago

Which value is needed to create a perfect square trinomial from the expression x2 + 8x + _____?

Mathematics

1 answer:

Alecsey [184]3 years ago

4 0

I believe it's +16, if you complete the square you'd have (x+4)^2 - 16 + a = 0 where a is the value you're looking for, so to make this correct you need a = 16

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(2x² - 5x-3)/ (x-3) DIvide the polynomials

Anika [276]

Answer:

2x + 1

Step-by-step explanation:

$\frac{(2x² - 5x-3)}{(x - 3)}$

Factor out 2x² - 5x-3

$\frac{(2x + 1)(x - 3)}{x - 3}$

divide x - 3 by x - 3

=> 2x + 1

Or another step

Step by Step Solution

STEP

Equation at the end of step 1

STEP

2x² - 5x - 3/ x - 3

Trying to factor by splitting the middle term

2.1 Factoring 2x² - 5x - 3

The first term is, 2x² its coefficient is 2 .

The middle term is, -5x its coefficient is -5 .

The last term, "the constant", is -3

Step-1 : Multiply the coefficient of the first term by the constant 2 • -3 = -6

Step-2 : Find two factors of -6 whose sum equals the coefficient of the middle term, which is -5 .

-6 + 1 = -5 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -6 and 1

2x² - 6x + 1x - 3

Step-4 : Add up the first 2 terms, pulling out like factors :

2x • (x-3)

Add up the last 2 terms, pulling out common factors :

1 • (x-3)

Step-5 : Add up the four terms of step 4 :

(2x+1) • (x-3)

Which is the desired factorization

Canceling Out :

2.2 Cancel out (x-3) which appears on both sides of the fraction line.

Final result :

2x + 1

6 0

2 years ago

Which expression is equivalent to...? Screenshots attached, please help.

BaLLatris [955]

For this case we must simplify the following expression:

$\sqrt [3] {64 * a ^ 6 * b ^ 7 * c ^ 9}$

We rewrite:

$64 = 4 ^ 3\\a ^ 6 = (a ^ 2) ^ 3\\b ^ 6 * b = ((b ^ 2) ^ 3 * b)\\c ^ 9 = (c ^ 3) ^ 3$

So:

$\sqrt [3] {4 ^ 3 * (a ^ 2) ^ 3 * (b ^ 2) ^ 3 * b * (c ^ 3) ^ 3} =\\\sqrt [3] {4 * a ^ 2 * b ^ 2 * c ^ 3) ^ 3 * b} =$

By definition of properties of powers and roots we have:

$\sqrt [n] {a ^ m} = a ^ {\frac {m} {n}}$

So:

$4a ^ 2b ^ 2 c ^ 3 \sqrt [3] {b}$

Answer:

Option B

3 0

3 years ago

Which statement is true about this argument? premises: if an angle measure is greater than 90°, then the angle is an obtuse angl

vazorg [7]

Answer: option d. the argument is valid by the law of detachment.

The law of detachment consists in make a conlcusion in this way:

Premise 1) a => b
Premise 2) a is true

Conclusion: Then, b is true

Note: the order of the premises 1 and 2 does not modifiy the argument.

IN this case:

Premise 1) angle > 90 => obtuse

Premise 2) angle = 102 [i.e. it is true that angle > 90]]

Conclusion: it is true that angle is obtuse

3 0

4 years ago

Read 2 more answers

A random sample of 85 group leaders, supervisors, and similar personnel at General Motors revealed that, on average, they spent

andreyandreev [35.5K]

Answer:

Step-by-step explanation:

From the information given,

Number of personnel sampled, n = 85

Mean or average = 6.5

Standard deviation of the sample = 1.7

We want to determine the confidence interval for the mean number of years that personnel spent in a particular job before being promoted.

For a 95% confidence interval, the confidence level is 1.96. This is the z value and it is determined from the normal distribution table. We will apply the following formula to determine the confidence interval.

z×standard deviation/√n

= 1.96 × 6.5/√85

= 1.38

The confidence interval for the mean number of years spent before promotion is

The lower end of the interval is 6.5 - 1.38 = 5.12 years

The upper end is 6.5 + 1.38 = 7.88 years

Therefore, with 95% confidence interval, the mean number of years spent before being promoted is between 5.12 years and 7.88 years

4 0

3 years ago

Jeremiah currently has an account balance of $1624.35. His initial deposit on the account was $975 and it earned 3.7% simple int

Naya [18.7K]

Current Account Balance = $1,624.35

Initial Deposit = $975

Interest Rate (Simple) = 3.7% simple interest

Interest Earned = Current Account Balance - Initial Deposit

⇒ Interest Earned = $1,624.35 - $975

⇒ Interest Earned = $649.35

Now the Formula for Simple Interest is:

Simple Interest = × $\frac{\text{P x R x T}}{100}$ , where P is the initial deposit, R is the rate of interest and T is the time period

⇒ 649.35 = $\frac{\text{975 x 3.7 x T}}{100}$

⇒ T = $\frac{\text{649.35 x 100}}{\text{975 x 3.7}}$

⇒ T = 18

Hence, Jeremiah has had the account for 18 years.

6 0

3 years ago