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3 years ago

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

1 answer:

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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Explain why a graph that fails the vertical-line test does not represent a function. Be sure to use the definition of a function

ArbitrLikvidat [17]

Explanation:

A function is a relationship where any one x-value/input only has <u>one </u>corresponding y-value/output. (note: a y-value can have multiple x-values).

> This can be called "assigning one y-value to every x element".

The vertical line test places a line that would connect all y-values of an x-value (that is, if it were to have multiple y-values). If multiple points can be found along the vertical line, it is, therefore, by the definition of a function, not a function. (Because an x-value will have more than one y-value).

So, a graph that fails the vertical-line test does not represent a function because an x-value will correspond with more than one y-value.

hope this helps!!

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2 years ago

The difference between 4x and 2x is 70. Find the 2x

VashaNatasha [74]

Answer:

2x = 70

Step-by-step explanation:

4x - 2x = 70

2x = 70

x = 70/2

x = 35

4 0

2 years ago

Please answer the question in the picture below

Elanso [62]

The answer is b because there is a negative in the exponent and the number needs to be a single digit and 54 is double digit. hope this helps!

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3 years ago

An international company has 22,600 employees in one country. If this represents 16.3% of the company’s employees, how many empl

Lady_Fox [76]

Answer:

sorry but I don't know the answer

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3 years ago

Read 2 more answers

Forty percent of households say they would feel secure if they had $50,000 in savings. you randomly select 8 households and ask

Kay [80]

Answer:

Let X be the event of feeling secure after saving $50,000,

Given,

The probability of feeling secure after saving $50,000, p = 40 % = 0.4,

So, the probability of not feeling secure after saving $50,000, q = 1 - p = 0.6,

Since, the binomial distribution formula,

$P(x=r)=^nC_r p^r q^{n-r}$

Where, $^nC_r=\frac{n!}{r!(n-r)!}$

If 8 households choose randomly,

That is, n = 8

(a) the probability of the number that say they would feel secure is exactly 5

$P(X=5)=^8C_5 (0.4)^5 (0.6)^{8-5}$

$=56(0.4)^5 (0.6)^3$

$=0.12386304$

(b) the probability of the number that say they would feel secure is more than five

$P(X>5) = P(X=6)+ P(X=7) + P(X=8)$

$=^8C_6 (0.4)^6 (0.6)^{8-6}+^8C_7 (0.4)^7 (0.6)^{8-7}+^8C_8 (0.4)^8 (0.6)^{8-8}$

$=28(0.4)^6 (0.6)^2 +8(0.4)^7(0.6)+(0.4)^8$

$=0.04980736$

(c) the probability of the number that say they would feel secure is at most five

$P(X\leq 5) = P(X=0) + P(X=1) + P(X=2) + P(X=3) + P(X=4) + P(X=5)$

$=^8C_0 (0.4)^0(0.6)^{8-0}+^8C_1(0.4)^1(0.6)^{8-1}+^8C_2 (0.4)^2 (0.6)^{8-2}+8C_3 (0.4)^3 (0.6)^{8-3}+8C_4 (0.4)^4 (0.6)^{8-4}+8C_5(0.4)^5 (0.6)^{8-5}$

$=0.6^8+8(0.4)(0.6)^7+28(0.4)^2(0.6)^6+56(0.4)^3(0.6)^5+70(0.4)^4(0.6)^4+56(0.4)^5(0.6)^3$

$=0.95019264$

8 0

3 years ago