Ask question

Ask question

All categories

3 years ago

5

Find the dimensions of a rectangle with perimeter 76 m whose area is as large as possible. m (smaller value) m (larger value)

1 answer:

Sladkaya [172]3 years ago

5 0

Answer:

19 m

Step-by-step explanation:

Perimeter = 2(length + width) ; P = 2(l+w) - - (1)

Area = Length * width ; A = l*w - - - (2)

76 = 2(l+w)

76/2 = l+w

l+w = 38

l = 38 - w

Put l = 38 - w in (1)

A = (38-w)*w

A = 38w - w²

At maximum point:

dA/dw = 0

dA/dw = 38 - 2w

38 - 2w = 0

38 = 2w

w = 38/2

w = 19

You might be interested in

Solve x2 – 4x – 9 = 29 for x.

Irina-Kira [14]

$x^2 - 4x - 9 = 29 \\ x^2 - 4x - 9 - 29 = 0 \\ x^2 - 4x - 38 = 0 \\ x= \frac{-b \pm \sqrt{ b^{2} -4ac} }{2a} 
$ ; where a = 1, b = -4 and c = -38
$x= \frac{-(-4) \pm 
\sqrt{ 
(-4)^{2} -4 \times 1 \times -38} }{2 \times 1} \\ = \frac{4 \pm \sqrt{ 16 +152} }{2} \\ =\frac{4 \pm \sqrt{ 168} }{2} \\ =\frac{4 \pm 
2\sqrt{42} }{2} \\ 
=2+\sqrt{42} \ or \ 2-\sqrt{42}\\=8.48 \ or \ -4.48$

8 0

3 years ago

Read 2 more answers

Is this inequality statement true? (Y or N) <br><br> -13 < -5

Kisachek [45]

Answer:

yes

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

Find the scale factor<br> A. 3.5<br> B. 3/5<br> C. 35

Serhud [2]

Answer:

3.5

Step-by-step explanation:

35/10 = 3.5

4 0

3 years ago

A storage shed is to be built in the shape of a (closed) box with a square base. It is to have a volume of 150 cubic feet. The c

Alenkinab [10]

Answer:

$C(s) = 6s^2 + \dfrac{1500}{s}\\\text{where s is the side of base.}$

Step-by-step explanation:

We are given the following in the question:

A storage shed is to be built in the shape of a (closed) box with a square base.

Volume = 150 cubic feet

Let s be the edge of square base and h be the height.

Volume of cuboid =

$l\times b\times h$

where l is the length, b is the base and h is the height.

Volume of box =

$s^2h = 150\\\\h = \dfrac{150}{s^2}$

Area of base =

$\text{side}\times \text{side} = s^2$

Cost of concrete for the base = $4

Cost of base($) = $4s^2$

Area of roof =

$\text{side}\times \text{side} = s^2$

Cost of material for the roof = $2

Cost of roof ($) = $2s^2$

Area of 4 walls =

$4\times (sh)\\=4sh$

Cost of material for the side = $2.50

Cost of material of side($) =

$2.50\times 4s(\dfrac{150}{s^2})\\\\=\dfrac{1500}{s}$

Total cost

= Cost of base + Cost of 4 sides + Cost of roof

$C(s) = 4s^2 + \dfrac{1500}{s} + 2s^2\\\\C(s) = 6s^2 + \dfrac{1500}{s}$

is the required cost function.

5 0

4 years ago

Can't get my head around this at all any help would be greatly appreciated.

chubhunter [2.5K]

Answer:

The input is -6, hope this helps :D

Step-by-step explanation:

Represent the machines as expressions:

outputA= 7x-6

outputB= 3x+2

Find the input when the outputA is 3*outputB:

outputA=3outputB

(7x-6)=3(3x+2)

7x-6=9x+6

2x=-12

x=-6

3 0

3 years ago

Read 2 more answers