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3 years ago

7

What is the solution to the equation? 2 x squared plus 4 equals 20 Choose all answers that are correct.

1 answer:

Stolb23 [73]3 years ago

8 0

$2x^2+4=20\ \ \ \ |subtract\ 4\ from\ both\ sides\\\\2x^2=16\ \ \ \ \ |divide\ both\ sides\ by\ 2\\\\x^2=8\iff x=\pm\sqrt8\\----------------------------\\\sqrt8=\sqrt{4\cdot2}=\sqrt4\cdot\sqrt2=2\cdot\sqrt2=2\sqrt2\ \ \ |use\ \sqrt{a\cdot b}=\sqrt{a}\cdot\sqrt{b}\\-----------------------------\\therefore\ your\ answer\ is\ -2\sqrt2\ and\ 2\sqrt2\to\boxed{a\ and\ c}$

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Which answer describes the type of sequence? 200, 40, 8, 1.6, ...

GalinKa [24]

Answer:

Option 1 the given sequence is a geometric.

Step-by-step explanation:

We have been given with the series

$200,40,8,1.6$

Arithmetic sequence is the sequence in which difference between consecutive terms is same that is common difference d

$d=a_2-a_1$

$d=40-200=-160$ here $a_2=40,a_1=200$

$d=8-40=-32$ here $a_2=8,a_1=40$

We can see the difference is not same

Hence, the given sequence is not arithmetic sequence.

Geometric sequence is the sequence in which ratio of consecutive terms is same that is common ratio r

$r=\frac{a_2}{a_1}$

$r=\frac{40}{200}=\frac{1}{5}$ here $a_2=40,a_1=200$

$r=\frac{8}{40}=\frac{1}{5}$ here $a_2=8,a_1=40$

$r=\frac{1.6}{8}=\frac{1}{5}$ here $a_2=1.6,a_1=8$

We can see the ratio is same.

Hence, given sequence is geometric

Therefore, Option 1 is correct given sequence is geometric.

7 0

3 years ago

Maggie opens a bank account with $15. She plans to put $5 in each week.

GenaCL600 [577]

Answer:

0 weeks - 15.00

1 weeks - 20.00

2 weeks - 25.00

3 weeks - 30.00

4 weeks - 35.00

5 weeks - 40.00

6 weeks - 45.00

7 weeks - 50.00

8 weeks - 55.00

9 weeks - 60.00

10 weeks - 65.00

Step-by-step explanation:

You just add 5 dollars everytime

4 0

3 years ago

What are the zeros of the function f(x) = x4 − x2 − 2?

goblinko [34]

Answer:

x = ± $\sqrt{2}$ , x = ± i

Step-by-step explanation:

f(x) = $x^{4}$ - x² - 2

to find the zeros , equate f(x) to zero , that is

$x^{4}$ - x² - 2 = 0

using the substitution u = x² , then

u² - u - 2 = 0 ← in standard form

(u - 2)(u + 1) = 0 ← in factored form

equate each factor to zero and solve for u

u - 2 = 0 ⇒ u = 2

u + 1 = 0 ⇒ u = - 1

convert u back into terms of x

x² = 2 ( take square root of both sides )

x = ± $\sqrt{2}$

x² = - 1 ( take square root of both sides )

x = ± $\sqrt{-1}$ = ± i

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2 years ago

at the local grocery store ,a 16-ounce bottle of apple juice costs$3.20 what is the cost of the apple juice

SashulF [63]

$3.20 trick question.

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3 years ago

A baseball team's starting lineup has 3 left handed hitters, 4 right-handed hitters, and 2 Switch Hitters. if there are a total

Ivenika [448]

Here's the link to the answer! Couldn't attach it here!

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3 years ago

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