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PSYCHO15rus [73]

3 years ago

13

Which of the following is a solution of x2 − 2x = −8? (6 points) Select one: a. negative 1 minus i square root of 28 b. 1 plus i

square root of 28 c. negative 1 minus i square root of 7 d. 1 plus i square root of 7

1 answer:

crimeas [40]3 years ago

3 0

X = 2 +- √4 -32 )/2 = 1 +-i√7

Answer is <span>d. 1 plus i square root of 7

Hope it helps!
</span>

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The points in the table lie on a line. Find the slope of the line.

AlexFokin [52]

Answer:

the slope is 1

Step-by-step explanation:

The slope can be found by determining the change in y over the change in x

In this graph as y goes up one x goes up one so the slope is 1/1 or 1

<em>The1AndOnlyMark</em>

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The quarterly returns for a group of 6161 mutual funds are well modeled by a Normal model with a mean of 6.16.1% and a standard

Shtirlitz [24]

Answer:

a) The cut off value of the highest 50% is 6.16%.

b) The cut off value of the highest 16% is 8.8%.

c) The cut off value of the lowest 2.5% is 0.7%.

d) The cut off values of the middle 68% is 3.4% for the lower bound and 8.8% for the higher bound.

Step-by-step explanation:

The 68–95–99.7 rule is an empirical rule to remember the percentage of values that lie within a band around the mean in a normal distribution with a width of two, four and six standard deviations respectively.

a) Cut off value of the highest 50%

It corresponds to the half that has the higher returns, which are the ones that are above the mean (0 standard deviation). The cut off value in this case is the mean x=6.16%.

b) Cut off value of the highest 16%

In this case, we use the 68 rule-value, which means that 68% of the values lies within a band around the mean with a width of two standard deviations.

The percentage that lies out of this band is 100%-68%=32%, of which 16% lies above the band (the highest 16%) and 16% lies below the band.

We can estimate, according to this rule, that the highest 16% are above the cutoff value X of μ+1σ:

$X=\mu+\sigma=6.1%+2.7%=8.8%$

The cut off value of the highest 16% is 8.8%.

c) Cut off of the lowest 2.5%

In this case, we use the 95 rule.

The lowest 2.5% lies below two standards deviation less of the mean

$X=\mu-2*\sigma=6.1%-2*2.7%=0.7%$

The cut off value of the lowest 2.5% is 0.7%.

d) Cut off of the middle 68%

In this case we calculate the band within one standard deviation.

$X_{low}=\mu-\sigma=6.1%-2.7%=3.4%\\\\X_{high}=\mu+\sigma=6.1%+2.7%=8.8%$

The cut off values of the middle 68% is 3.4% for the lower bound and 8.8% for the higher bound.

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3 years ago

Lines A, B, and C show proportional relationships.

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For line A,

if we increase x by 1 unit then y increases by 4 units i.e. (1,3) and similarly another point becomes

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For line B,

if we increase x by 1 uni then y also increases by 1 unit i.e ( 1,1) and similarly another points becomes (2,2),(3,3),(4,4), etc.

For line C,

if we increase x by 3 units then y increases by 1 units i.e.(3,1) and similarly another points becomes

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In above lines, the value of x is exactly equal to that of y in line B.

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A gardener wants to compare the heights of plants in two gardens that are watered using different tools. The heights, in centime

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Garden A: 24.05cm ( add all the numbers(=457)and divide by the amount of numbers (19))

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3 years ago

Solve the inequality t/4 >7<br> And 2c/3 +1>7

Maru [420]

Answer: c > 12

Step-by-step explanation:tep 1 :

c

Simplify —

3

Equation at the end of step 1 :

c

((2 • —) - 1) - 7 > 0

3

Step 2 :

Rewriting the whole as an Equivalent Fraction :

2.1 Subtracting a whole from a fraction

Rewrite the whole as a fraction using 3 as the denominator :

1 1 • 3

1 = — = —————

1 3

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

2.2 Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

2c - (3) 2c - 3

———————— = ——————

3 3

Equation at the end of step 2 :

(2c - 3)

———————— - 7 > 0

3

Step 3 :

Rewriting the whole as an Equivalent Fraction :

3.1 Subtracting a whole from a fraction

Rewrite the whole as a fraction using 3 as the denominator :

7 7 • 3

7 = — = —————

1 3

Adding fractions that have a common denominator :

3.2 Adding up the two equivalent fractions

(2c-3) - (7 • 3) 2c - 24

———————————————— = ———————

3 3

Step 4 :

Pulling out like terms :

4.1 Pull out like factors :

2c - 24 = 2 • (c - 12)

Equation at the end of step 4 :

2 • (c - 12)

———————————— > 0

3

Step 5 :

5.1 Multiply both sides by 3

5.2 Divide both sides by 2

Solve Basic Inequality :

5.3 Add 12 to both sides

c > 12

Inequality Plot :

5.4 Inequality plot for

0.667 X - 8.000 > 0

One solution was found :

c > 12

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3 years ago