All categories

3 years ago

How can you find f(3) if f(x) = -2x2 – 4?

Mathematics

2 answers:

Julli [10]3 years ago

8 0

Answer: f(3)=-20

Step-by-step explanation:

If you look at f(x) and f(3), you can see that 3 is in place of x. That means when x=3, what is f(x). You plug in x=3 into f(x) and solve.

f(3)=-2(3)²-2

f(3)=-2(9)-2

f(3)=-18-2

f(3)=-20

Citrus2011 [14]3 years ago

8 0

Answer:

-20

Step-by-step explanation:

You might be interested in

How do I write 770,070 in expanded form

beks73 [17]

7x100,000+7x10,000+7x10

8 0

2 years ago

In a sample of 60 electric motors, the average efficiency (in percent) was 85 and the standard deviation was 2. Section 05.01 Ex

jasenka [17]

Answer:

95% confidence interval for the mean efficiency is [84.483 , 85.517].

Step-by-step explanation:

We are given that in a sample of 60 electric motors, the average efficiency (in percent) was 85 and the standard deviation was 2.

So, the pivotal quantity for 95% confidence interval for the population mean efficiency is given by;

P.Q. = $\frac{\bar X - \mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\mu$ = sample average efficiency = 85

$\sigma$ = sample standard deviation = 2

n = sample of motors = 60

$\mu$ = population mean efficiency

So, 95% confidence interval for the mean efficiency, $\mu$ is ;

P(-2.0009 < $t_5_9$ < 2.0009) = 0.95

P(-2.0009 < $\frac{\bar X - \mu}{\frac{s}{\sqrt{n} } }$ < 2.0009 ) = 0.95

P( $-2.0009 \times {\frac{s}{\sqrt{n} }$ < ${\bar X - \mu}$ < $2.0009 \times {\frac{s}{\sqrt{n} }$ ) = 0.95

P( $\bar X -2.0009 \times {\frac{s}{\sqrt{n} }$ < $\mu$ < $\bar X +2.0009 \times {\frac{s}{\sqrt{n} }$ ) = 0.95

95% confidence interval for $\mu$ = [ $\bar X -2.0009 \times {\frac{s}{\sqrt{n} }$ , $\bar X +2.0009 \times {\frac{s}{\sqrt{n} }$ ]

= [ $85 -2.0009 \times {\frac{2}{\sqrt{60} }$ , $85 +2.0009 \times {\frac{2}{\sqrt{60} }$ ]

= [84.483 , 85.517]

Therefore, 95% confidence interval for the population mean efficiency is [84.483 , 85.517].

8 0

2 years ago

Make a table of values for the following equation:

mars1129 [50]

Answer:

Step-by-step explanation:

We choose arbitrary values for x and in each case calculate y = 2x + 5.

If x = 0, y = 5; if x = 3, y = 11, and so on.

How? when x = 3, y = 2(3) + 5 = 6 + 5 = 11.

The table, with rows and columns suitable to this problem, would look like:

x y

0 5

3 11

10 25

and so on

7 0

1 year ago

Read 2 more answers

What are the x-intercept and y-intercept of the graph of y=13x−6 ?

mestny [16]

Answer:

x intercept is 6/13

y intercept is -6

Step-by-step explanation:

x intercepted when y is zero.

y intecepted when x is zero...

3 0

3 years ago

What are the solutions to the quadratic equation (5y + 6)2 = 24? y = and y = y = and y = y = and y = y = and y =

satela [25.4K]

The correct result would be y = -6/5 - (2 * sqrt(6))/5 and y = (2 * sqrt(6))/5 - 6/5.

8 0

2 years ago

Read 2 more answers