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2 years ago

Given f(x) = -2x– 9x + 7, what is the value of f(-3)?

Mathematics

2 answers:

RSB [31]2 years ago

6 0

Answer:

Step-by-step explanation:

Y =

y=−2x−9x+7

Y = −11x+7

_________________________

X =

Let's solve for x.

y=−2x−9x+7

−11x+7=y

−11x+7+−7=y+−7

−11x=y−7

-11x/11 = y-7/-11

X = -11x/11 = y-7/-11

Kamila [148]2 years ago

3 0

Answer:

f(- 3) = 40

Step-by-step explanation:

To evaluate f(- 3), substitute x = - 3 into f(x), that is

f(- 3) = - 2(- 3) - 9(- 3) + 7 = 6 + 27 + 7 = 40

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State tax is computed by first subtracting the amount of exemptions (5*$1000=$5000) from annual income and then multiplying it by the state tax.

($18150-$5000)*5%= $657.50

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3 years ago

What is the probability that 1 or 2 are rolled on a number cube with sides numbered 1, 2, 3, 4,

choli [55]

Answer: $\frac{1}{3}$

Step-by-step explanation:

total sides = 6

p (rolling a 1) = $\frac{1}{6}$

p (rolling a 2) = $\frac{1}{6\\}$

Note:

or - add

and - multiply

∴ $\frac{1}{6} +\frac{1}{6} = \frac{2}{6}$

∴ $\frac{2}{6} = \frac{1}{3}$

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2 years ago

What is 9 x 100 + 8 x 10 + 7 x 1000

mr Goodwill [35]

Answer:

9 x 100 + 8 x 10 + 7 x 1000 = 7,980

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2 years ago

How heavy a load (pounds) is needed to pull apart pieces of wood 4 inches long and 1.5 inches square? Here are data from student

statuscvo [17]

Answer:

a. (29526.192 , 32155.808)

b. (29673.9301 , 32008.0699)

Step-by-step explanation:

on calculation, we find that sample mean = 30843 and sample standard deviation = 3018.504, and n=20

Sample Mean = 30841

SD = 3000

Sample Size (n) = 20

Standard Error (SE) = SD/root(n) = 670.8204

alpha (a) = 1 - 0.95 = 0.05

z critical value for 95% confidence interval:

z(a/2) = z(0.025) = 1.96

Margin of Error (ME) = z(a/2) x SE = 1314.808

95% confidence interval is given by:

Sample Mean +/- (Margin of Error) = 30841 +/- 1314.808

= (29526.192 , 32155.808)

2)when std dev of population is not known, we use sample's, but we have to use t instead of z

Sample Mean = 30841

SD = 3018.504

Sample Size (n) = 20

Standard Error (SE) = SD/root(n) = 674.958

alpha (a) = 1-0.9 = 0.1

we use t-distribution as population standard deviation is unknown

t(a/2, n-1 ) = 1.7291

Margin of Error (ME) = t(a/2,n-1)x SE = 1167.0699

90% confidence interval is given by:

Sample Mean +/- (Margin of Error)

30841 +/- 1167.0699 = (29673.9301 , 32008.0699)

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3 years ago

What is the volume of corn held in this cone-shaped grain silo? Use 3.14 for π and round to the nearest cubic foot. Enter your a

babymother [125]

Answer:

V = 301 ft^3

Step-by-step explanation:

The volume of a cone is given by

V =1/3 pi r^2 h

We know pi = 3.14 r =6 and

We need to determine h

We can find h from the Pythagorean theorem where 6 is a leg and 10 is the hypotenuse

h^2 +6^2 = 10^2

h^2 +36 = 100

h^2 = 64

Taking the square root of each side

h = 8

V =1/3 pi r^2 h

V = 1/3 (3.14) (6)^2 * 8

V = 301.44 ft^3

Rounding to the nearest cubic foot

V = 301 ft^3

7 0

3 years ago

Read 2 more answers