Ask question

Ask question

All categories

3 years ago

9

The perimeter of a rectangle is 30 cm the length is 9 cm long longer than the width what are the length and width of the rectang

le

1 answer:

adell [148]3 years ago

8 0

Step-by-step explanation:

perimeter = 2(length) + 2(width)

let x represent the width of the rectangle

$30 = 2x + 2(x + 9)$

$30 = 4x + 18$

$12 = 4x$

$x = 3$

therefore width = 3 cm

length = 3+9

= 12cm

You might be interested in

A supermarket sells two flavors of cereal: a fruit flavor and a chocolate flavor. In a market survey, the event that a customer

Sedaia [141]

This is a binomial distribution.
p = 0.71, q = 1 - p = 1 - 0.71 = 0.29, n = 20

P(x ≤ 19) =1 - P(x = 20) = 1- 20C20 x (0.71)^(20 - 20) x (0.29)^20 = 1 - 0.29^20 = 1 - 0 = 1

4 0

3 years ago

Mrs Andrew's pays $125. For a hair cut. If she gives a 25% tip, how much will she pay

belka [17]

Answer:

$156.25

Step-by-step explanation:

25% of 125 is 31.25. So 125+31.25 is 156.25.

4 0

3 years ago

A group of mathematical symbols that express a relationship or that are used to solve a problem

pogonyaev

A group of mathematical symbols that express a relationship or that are used to solve a problem is a FORMULA

8 0

3 years ago

Please help me with this problem and if you can show your work

ella [17]

Answer:

2.9

just answering wrong because i need points sorry

7 0

3 years ago

Find a positive number for which the sum of it and its reciprocal is the smallest (least) possible. Let x be the number and let

Allisa [31]

Answer:

$S(x) = x + \frac{1}{x}$ --- Objective function

Interval = $\{x:x=1\}$

Step-by-step explanation:

Given

Represent the number with x

The required sum can be represented as:

$x + \frac{1}{x}$

Hence, the objective function is:

$S(x) = x + \frac{1}{x}$

To get the the interval, we start by differentiating w.r.t x

<em>Using first principle, this gives:</em>

$S'(x) = 1 - \frac{1}{x^2}$

Equate S'(x) to 0 in order to solve for x

$0 = 1 - \frac{1}{x^2}$

Subtract 1 from both sides

$0 -1 = 1 -1 - \frac{1}{x^2}$

$-1 = - \frac{1}{x^2}$

Multiply both sides by -1

$1 = \frac{1}{x^2}$

Cross Multiply

$x^2 * 1 = 1$

$x^2 = 1$

Take positive square root of both sides because x is positive

$\sqrt{x^2} = \sqrt{1$

$x = 1$

Representing x using interval notation, we have

Interval = $\{x:x=1\}$

To get the smallest sum, we substitute 1 for x in $S(x) = x + \frac{1}{x}$

$S(1) = 1 + \frac{1}{1}$

$S(1) = 1 + 1$

$S(1) = 2$

<em>Hence, the smallest sum is 2</em>

3 0

3 years ago