Use elimination method - I am eliminaing the y-variable.

1(5x + 8y = 16) → 5x + 8y = 16
4(6x - 2y = 54) → 24x - 8y = 216
Add equations: 29x = 232
Divide by 29: x = 8

Answer: x = 8

7 0

3 years ago

Un olivar tiene 80 olivos. Sesenta de ellos dan, por término medio, 50 kg 4 hg 60 dag 5 g de aceitunas cada uno, y los otros vei

vlada-n [284]

Answer:

1330.808 euros

Step-by-step explanation:

Let's first calculate the total amount of kilograms,

for the first 60, we have to:

50 kg

4 hg = 0.5 kg

60 dag = 0.6

5 g = 0.005 kg

adding: 50 + 0.5 +0.6 + 0.005 = 51.105 kg per tree, but they are 60

51.105 * 60 = 3066.3

now for the other 20:

53 kg

2 hg = 0.2 kg

16 dag = 0.16

5 g = 0.005

adding: 53 + 0.2 +0.16 + 0.005 = 53.365 kg per tree, but they are 20

53,365 * 20 = 1067.3

in total it would be: 3066.3 + 1067.3 = 4133.6

they tell us that 1/5 is the quantity in liters:

4133.6 * 1/5 = 826.72 liters

so to calculate the earnings it would be:

2.65 * 826.72 - 860 = 1330.808

which means that in net earnings are 1330.808 euross

8 0

3 years ago

Among all right circular cones with a slant height of 24, what are the dimensions (radius and height) that maximize the volum

aleksklad [387]

Answer:

5571.99

Step-by-step explanation:

We need to use the Pythagorean theorem to solve the problem.

The theorem indicates that,

$r^2+h^2=24^2 \\r^2+h^2=576\\r^2=576-h^2$

Once this is defined, we proceed to define the volume of a cone,

$v=\frac{1}{3}\pi r^2 h$

Substituting,

$v=\frac{1}{3} \pi (576-h^2)h\\v=\frac{1}{3} \pi (576h-h^3)$

We need to find the maximum height, so we proceed to calculate h, by means of its derivative and equalizing 0,

$\frac{dv}{dh} = \frac{1}{3} \pi (576-3h^2)$

$\frac{dv}{dh} = 0$ then $\rightarrow \frac{1}{3}\pi(576-3h^2)=0$

$h_1=-8\sqrt{3}\\h_2=8\sqrt{3}$

<em>We select the positiv value.</em>

We have then,

$r^2 = 576-(8\sqrt3)^2 = 384\\r=\sqrt{384}$

We can now calculate the maximum volume,

$V_{max}= \frac{1}{3}\pi r^2 h = \frac{1}{3}\pi (\sqrt{384})^2 (8\sqrt{3}) = 5571.99$

4 0

3 years ago