Ask question

Ask question

All categories

3 years ago

15

The roots of a quadratic function are -2 and -6

1 answer:

PSYCHO15rus [73]3 years ago

5 0

Step-by-step explanation:

The factors are x + 2 and x + 6.

You might be interested in

postnew [5]

♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️

$(3 \times 25 )+ 60 = 75 + 60 =$

$135$

Thus Lisa spent 135 $ .

♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️

3 0

3 years ago

Read 2 more answers

How many people were surveyed in the bar graph 9 30 18 25

Helga [31]

Answer:

30

Step-by-step explanation:

9 + 9 + 6 + 5 + 1 = 30

5 0

3 years ago

In a data distribution, the first quartile, the median and the means are 30.8, 48.5 and 42.0

kolbaska11 [484]

Answer:

$Q_3 = 56.45$ --- The third quartile

$Var = 370.18$ -- Variance

Step-by-step explanation:

Given

$Q_1 = 30.8$ -- First quartile

$Q_2 = 48.5$ --- Median

$\bar x = 42$ --- Mean

$Skp = -0.38$ --- Coefficient of skewness

Solving (9): The third quartile $Q_3$

This is calculated from

$Skp = \frac{Q_1 + Q_3 - 2Q_2}{Q_3 - Q_1}$

So, we have:

$-0.38 = \frac{30.8 + Q_3- 2*48.5}{Q_3 - 30.8}$

Cross Multiply

$-0.38 (Q_3 - 30.8)= 30.8 + Q_3- 2*48.5$

Open bracket

$-0.38Q_3 + 11.704= 30.8 + Q_3- 97.0$

Collect like terms

$-0.38Q_3 -Q_3= 30.8 - 97.0- 11.704$

$-1.38Q_3= -77.904$

Divide both sides -1.38

$Q_3 = \frac{-77.904}{-1.38}$

$Q_3 = 56.45$ --- approximated

Solving (b): The variance

First, calculate the standard deviation from:

$3IQR = 4SD$

$IQR= Q_3 - Q_1$

So:

$3IQR = 4SD$

$3(Q_3 - Q_1) = 4SD$

Make SD the subject

$SD = \frac{3}{4}(Q_3 - Q_1)$

$SD = \frac{3}{4}(56.45 - 30.8)$

$SD = \frac{3}{4}*25.65$

$SD = \frac{3*25.65}{4}$

$SD = \frac{76.95}{4}$

$SD = 19.24$

So, the variance is:

$Var = SD^2$

$Var = 19.24^2$

$Var = 370.18$

5 0

3 years ago

Simplify. (-√7)(-√7)

Savatey [412]

Answer:

<em><u>7</u></em>

Step-by-step explanation:

(-√7)(-√7)

$(-\sqrt{7})^2$

$(\sqrt{7})^2$

<em><u>7</u></em>

<em><u /></em>

<em><u>Please Mark As Brainliest</u></em>

5 0

3 years ago

A model rocket launched directly upward at a speed of 16 meters per second from a helght of 2 meters . The f(t) = - 4.9t ^ 2 + 1

Anton [14]

Answer:

f(t) = 15.06 m

Step-by-step explanation:

The relationship between the height of the rocket and the time after launch, t. In seconds is given by :

$f(t) = - 4.9t ^ 2 + 16t + 2$

We need to find the maximum height the rocket will reach the ground.

When it reaches the ground,

f(t) = 0

So,

Maximum height,

f'(t) = 0

$-9.8t+16=0\\\\t=\dfrac{16}{9.8}\\\\t=1.63\ s$

Put t = 1.63 in equation (1).

$f(1.63) = - 4.9\times (1.63 ^ 2) + 16(1.63) + 2\\\\=15.06\ m$

So, the maximum height of the rocket is 15.06 m.

4 0

3 years ago