All categories

3 years ago

F(x)=3x^2 +x find f(-5)

Mathematics

1 answer:

Dovator [93]3 years ago

8 0

Answer:

-225

Step-by-step explanation:

f(-5)= 3(-5)^2

f(-5)= -15^2

-225

You might be interested in

What is how do I find m and b?

IrinaK [193]

Answer:

Step-by-step explanation:

The slope-intercept form of an equation of a line:

$y=mx+b$

m - slope

b - y-intercept → (0, b)

The formula of a slope:

$m=\dfrac{y_2-y_1}{x_2-x_1}$

=====================================

From the table we have y-intercept (0, 5) → b = 5 and other point (1, 26).

Calculate the slope:

$m=\dfrac{26-5}{1-0}=\dfrac{21}{1}=21$

8 0

3 years ago

A sample of students from an introductory psychology class were polled regarding the number of hours they spent studying for the

Anni [7]

Answer:

$8.68,13.16$

Step-by-step explanation:

Hint- First we have to calculate the mean and standard deviation of the sample and then applying formula for confidence interval we can get the values.

Mean of the sample is,

$\mu=\dfrac{\sum _{i=1}^{24}a_i}{24}=\dfrac{262}{24}=10.92$

Standard deviation of the sample is,

$\sigma =\sqrt{\dfrac{\sum _{i=1}^{24}\left(x_i-10.92\right)^2}{24-1}}=5.6$

The confidence interval will be,

$=\mu \pm Z\dfrac{\sigma}{\sqrt{n}}$

Here,

Z for 95% confidence interval is 1.96, and n is sample size which is 24.

Putting the values,

$=10.92 \pm 1.96\cdot \dfrac{5.6}{\sqrt{24}}$

$=10.92 \pm 2.24$

$=8.68,13.16$

Confidence interval is used to express the degree of uncertainty associated with a sample.

95% confidence interval means that if we used the same sampling method to select different samples and calculate an interval, we would expect the true population parameter to fall within the interval for 95% of the time.

5 0

3 years ago

The base of a regular pyramid is a hexagon. The figure shows a regular hexagon with center C. An apothem is shown as a dashed se

tatuchka [14]

Answer: 294√3

Explanation:

1) The described hexagon has these featrues:
a) 6 congruent equilateral triangles whose side lengths measure 14
b) height of each triangle = apotema = a
c) the area of each triangle is base × a / 2 = 14 × a / 2 = 7a

2) a is one leg of a right triangle whose other leg is 14 / 2 = 7, and the hypotenuse is 14.

3) Then you can use Pythagorean theorem fo find a:

14² = 7² + a² ⇒ a² = 14² - 7² = 147 ⇒ a = √ 147 = 7√3

4) Therefore, the area of one triangle is: 14 × 7√3 / 2 = 49√3

5) And the area of the hexagon is 6 times that: 6 × 49√3 = 294√3

8 0

3 years ago

Consider these scenarios. 1. A piano weighs 5.5 × 102 units. 2. A grain of salt weighs 1.02 × 10-3 units. 3. A tractor trail

zhannawk [14.2K]

Answer:

1) pounds

2) grams

3) tons

Step-by-step explanation:

The suitable measurements for the scenarios are:

1) A piano weighs 5.5 × 10² units

550 Ib (pounds)