Let f(x)= 13x + 7 and (x) = x^2-3x find ( f+g)(x)

Compute the value of the discriminant and give the number of real solutions of the quadratic equation.

Sergio039 [100]

$-2x^2+6x-3=0 \\ \\
a=-2 \\ b=6 \\ c=-3 \\ \Delta=b^2-4ac=6^2-4 \times (-2) \times (-3)=36-24=12$

The value of the discriminant is 12.
Since the discriminant is greater than zero, the equation has two real solutions.

4 0

3 years ago

What do you need to know?

cupoosta [38]

Answer:

incorrect

Step-by-step explanation:

the volume of a cube = s³ ( where s is the length of the side )

to find s take the cube root

s = $\sqrt[3]{27}$ = 3

since 3 × 3 × 3 = 27

4 0

3 years ago

I mark brianlest just help me;-;

Rina8888 [55]

Answer:

B)113.04 cm^2

Step-by-step explanation:

8 0

2 years ago

Read 2 more answers

A sample survey is designed to estimate the proportion of sports utility vehicles being driven in the state of California. A ran

mart [117]

Answer:

a) The 95% confidence interval would be given (0.070;0.121).

b) "increase the sample size n"

"decrease za/2 by decreasing the confidence"

Step-by-step explanation:

Notation and definitions

$X=48$ number of vehicles classified as sports utility.

$n=500$ random sample taken

$\hat p=\frac{48}{500}=0.096$ estimated proportion of vehicles classified as sports utility vehicles.

$p$ true population proportion of vehicles classified as sports utility vehicles.

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{\hat p(1-\hat p)}{n}})$

(a) Use a 95% confidence interval to estimate the proportion of sports utility vehicles in California. (Round your answers to three decimal places.)

The confidence interval would be given by this formula :

$\hat p \pm z_{\alpha/2} \sqrt{\frac{\hat p(1-\hat p)}{n}}$

For the 95% confidence interval the value of $\alpha=1-0.5=0.05$ and $\alpha/2=0.025$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=1.96$

And replacing into the confidence interval formula we got:

$0.096 - 1.96 \sqrt{\frac{0.096(1-0.096)}{500}}=0.070$

$0.096 + 1.96 \sqrt{\frac{0.096(1-0.096)}{500}}=0.121$

And the 95% confidence interval would be given (0.070;0.121).

We are confident (95%) that about 7.0% to 12.1% of vehicles in California are classified as sports utility .

(b) How can you estimate the proportion of sports utility vehicles in California with a higher degree of accuracy? (HINT: There are two answers. Select all that apply.)

For this case we just have two ways to increase the accuracy one is "increase the sample size n" since if we have a larger sample size the estimation would be more accurate. And the other possibility is "decrease za/2 by decreasing the confidence" because if we decrease the confidence level the interval would be narrower and accurate

7 0

3 years ago

A masonry contractor is preparing an estimate for building a stone wall and gate. He estimates that the job will take a 40-hour

kodGreya [7K]

Solution: Estimated time for the work is 40 hour work week.

Estimated payment to 3 laborers working 40 hours at cost $14 per hour is:

$3\times 40\times 14=$ $1680