F(x)=3x^2+8x+5 find value of f(a)

Three tickets to a concert cost $54. How much do 7 tickets cost? A. $58 B. $72 C. $108 D. $126

Ksju [112]

The answer is D $126,if three cost $54 that means one costs $18 and just multiply it with seven

7 0

3 years ago

The temperature of a weather station was 12.8 °F at midnight and fell 1.4 °F each hour for six hours. Which of the following sol

Len [333]

Answer:

Let's try to find a linear relation like:

T(h) = a*h + b

where a is the slope and b is the y-intercept.

h is the number of hours after midnight.

T is the temperature at the time defined by h.

We know that at midnight, the temperature is 12.8°F.

At midnight, we have h = 0, then:

T(0) = a*0 + b = 12.8°F

b = 12.8°F

Now we know that our function is:

T(h) = a*h + 12.8°F

We also know that the temperature fell 1.4 °F each hour for six hours.

Then the slope will be -1.4°F

We can write the linear relationship as:

T(h) = -1.4°F*h + 12.8°F (for 0 ≤ h ≤ 6)

Where we have a restriction in the possible values of h, because we know that this model only works for six hours after midnight,

3 0

3 years ago

Read 2 more answers

Could someone please help me with this problem and possibly explain if you can? (Will give up brainiest answer if correct, if po

Andrej [43]

To find the answer you need to find the square root of e^2 to get e so what you do to one side of the equation you do to the other side of the equation so find the square root of 0.36.
e=positive or negative 0.6

3 0

3 years ago

What is the solution to the system of equations -8x + 4y = -2, 2y = 1

Black_prince [1.1K]

Answer:

Hi! The correct answer is x=1/4+y/2!

Step-by-step explanation:

Solve for the first variable in one of the equations, then substitute the result into the other equation

5 0

3 years ago

A public bus company official claims that the mean waiting time for bus number 14 during peak hours is less than 10 minutes. Kar

ch4aika [34]

Answer:

We conclude that the mean waiting time is less than 10 minutes.

Step-by-step explanation:

We are given that a public bus company official claims that the mean waiting time for bus number 14 during peak hours is less than 10 minutes.

Karen took bus number 14 during peak hours on 18 different occasions. Her mean waiting time was 7.8 minutes with a standard deviation of 2.5 minutes.

Let $\mu$ = mean waiting time for bus number 14.

So, Null Hypothesis, $H_0$ : $\mu \geq$ 10 minutes {means that the mean waiting time is more than or equal to 10 minutes}

Alternate Hypothesis, $H_A$ : $\mu$ < 10 minutes {means that the mean waiting time is less than 10 minutes}

The test statistics that would be used here One-sample t test statistics as we don't know about the population standard deviation;

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

where, $\bar X$ = sample mean waiting time = 7.8 minutes

s = sample standard deviation = 2.5 minutes

n = sample of different occasions = 18

So, test statistics = $\frac{7.8-10}{\frac{2.5}{\sqrt{18} } }$ ~ $t_1_7$

= -3.734

The value of t test statistics is -3.734.

Now, at 0.01 significance level the t table gives critical value of -2.567 for left-tailed test.

Since our test statistic is less than the critical value of t as -3.734 < -2.567, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the mean waiting time is less than 10 minutes.

5 0

3 years ago