All categories

3 years ago

Find the maxmium area of a rectangular plot of land which can be enclosed by rope of length 60 metres

Mathematics

1 answer:

mario62 [17]3 years ago

3 0

Answer:

225 m²

Step-by-step explanation:

If W is the width of the rectangle, and L is the length, then:

60 = 2W + 2L

A = WL

Use the first equation to solve for one of the variables:

30 = W + L

L = 30 − W

Substitute into the second equation:

A = W (30 − W)

A = 30W − W²

This is a parabola, so we can find the vertex using the formula x = -b/(2a).

W = -30 / (2 × -1)

W = 15

Or, we can use calculus:

dA/dW = 30 − 2W

0 = 30 − 2W

W = 15

Solving for L:

L = 30 − W

L = 15

So the maximum area is:

A = WL

A = (15)(15)

A = 225

You might be interested in

On 5 days, lisa swam 650 meters, 675 meters, 725 meters, 800 meters, and 900 meters. What was her average distance per day?

zlopas [31]

Answer:

Her average per day was 750 meters.

Step-by-step explanation:

To find the average, add all the numbers up in the set and divide by how many numbers there are.

650 + 675 + 725 + 800 + 900 = 3750. Divide it by 5 and you get 750

6 0

2 years ago

Read 2 more answers

Triangle X Y Z is shown. Angle X Z Y is a right angle. Angle Z X Y is 60 degrees and angle X Y Z is 30 degrees. The length of hy

vladimir1956 [14]

Answer:

StartFraction StartRoot 3 EndRoot Over 3 EndFraction

Step-by-step explanation:

see the attached figure to better understand the problem

step 1

we know that

In the right triangle XYZ

$cos(Y)=\frac{ZY}{XY}$ ---> adjacent side divided by the hypotenuse

substitute the values

$cos(30\°)=\frac{ZY}{4}$

Remember that

$cos(30\°)=\frac{\sqrt{3}}{2}$

substitute

$\frac{\sqrt{3}}{2}=\frac{ZY}{4}$

$ZY=(4)\frac{\sqrt{3}}{2}$

$ZY=2\sqrt{3}\ units$

step 2

$sin(Y)=\frac{XZ}{XY}$ --> opposite side divided by the hypotenuse

substitute the values

$sin(30\°)=\frac{XZ}{4}$

Remember that

$sin(30\°)=\frac{1}{2}$

$\frac{1}{2}=\frac{XZ}{4}$

$XZ=2\ units$

step 3

$tan(Y)=\frac{XZ}{ZY}$ --> opposite side divided by adjacent side

substitute the values

$tan(Y)=\frac{2}{2\sqrt{3}}$

$tan(Y)=\frac{1}{\sqrt{3}}$

Simplify

$tan(Y)=\frac{\sqrt{3}}{3}$

StartFraction StartRoot 3 EndRoot Over 3 EndFraction

7 0

3 years ago

Read 2 more answers

A fruit company delivers its fruit in two types of boxes: large and small. a delivery of 5 large boxes and 3 small boxes has a t

Hoochie [10]

Let's let the weight of a large box be L, and the weight of a small box be S.

We know that 5 large boxes and 3 small boxes is 120kg, so:
5L + 3S = 120

We also know that 7 large boxes and 9 small boxes is 234kg, so:
7L + 9S = 234

You can multiply the first equation by 3 to get:
15L + 9S = 360

See how now both equations have 9S? We can now subtract one from the other:
(15L+9S) - (7L+9S) = 360-234
8L = 126
L = 15.75

Now sub this value back into an equation:
(5x15.75) + 3S = 120
3S = 41.25
S = 13.75

Double check these values
(7x15.75) + (9x13.75)
= 110.25 + 123.75
=234, which is consistent with above.

So a large box is 15.75kg, and a small box is 13.75kg.

Hope this helped

5 0

3 years ago

-3.6,-5.4,-8.1,-12.15 arithmetic or geometric or neither.

Brums [2.3K]

Answer:

Geometric Sequence

Step-by-step explanation:

1. Check the difference.

The difference between the 1st and 2nd term

$( - 5.4) - ( - 3.6) = - 1.8$