All categories

3 years ago

The length of a rectangle is 7 inches less than twice the width, w, of the rectangle.

Mathematics

1 answer:

Ivan3 years ago

4 0

Answer:

Step-by-step explanation:

Let w represent the width of the rectangle.

The length of a rectangle is 7 inches less than twice the width, w, of the rectangle. It means that the length is (2w - 7) inches

Part A

The function that gives the area as a function of the width is

A(w) = w(2w - 7)

Part B:

If the area of the rectangle is 60 square inches, it means that

w(2w - 7) = 60

2w² - 7w = 60

2w² - 7w - 60 = 0

2w² + 8w - 15w - 60 = 0

2w(w + 4) - 15(w + 4) = 0

2w - 15 = 0 or w + 4 = 0

w = 15/2 or w = - 4

Since w cannot be negative, then

w = 15/2 = 7.5 inches

You might be interested in

There are many ways to measure the reading ability of children. Research designed to improve reading performance is dependent on

ELEN [110]

Answer:

A 90% confidence interval to estimate the mean DRP score in Henrico County Schools is =32±2.7280

i.e. C.I. [29.3,34.7]

Hence the results are not significant.

Step-by-step explanation:

Given:

Total no of students =44

True mean =32

Standard deviation=11

And all 4 students score also given.

To Find:

90 % confidence interval and conclusion on it.

Solution:

Here for C.I. we required mean, standard deviation and no of students.

So mean =32,S.D.=11 and n=44

Therefore , For 90 % interval Zscore is Z=1.645

C.I.=mean±Z[Standard deviation/Sqrt(n)]

=32±1.645[11/Sqrt(44)]

=32±1.645[1.6583]

=32±2.7280

i.e. C.I. [29.3,34.7]

Now Here to commit on calculated interval we should check value of Z-score

So we need to calculate the sample mean.

Sample mean =Sum of all values /Total no of values.

=[40+ 26 +39+ 14+ 42+ 18 +25+ 43+ 46 +27 +19+ 47+ 19 +26+ 35 +34+ 15+ 44 40+ 38+ 31+ 46 +52 +25+ 35 +35+ 33 +29 +34 +41 +49+ 28+ 42+ 47 +35 +48 +22 33+ 41 +51 +27 +14+ 54 +45]/44

=34.86

Z-score=(sample mean -true mean)/[standard deviation/Sqrt(n)]

=(34.86-32)/[11/Sqrt(44)]

Z=1.72465

For ,

P(Z≥1.72465)=0.08544

For 0.05 significance level the results are not significant at p<0.01.

Researcher claimed mean is not correct upto 0.05 significant level

i.e calculated mean and Sample mean are different.

Hence the results are not significant.

6 0

3 years ago

Sum of the numbers m and n decreased by their product; write the algebraic expression

Oduvanchick [21]

<h3>Answer: m+n-mn</h3>

You can write mn as m*n

=================================

Explanation:

The sum is the result of adding two or more numbers. Saying the sum of m and n means m+n.

Then we subtract off the product of m and n. The product is the result of multiplying m and n. We say m*n or mn to indicate their product.

Overall, we end up with m+n-mn

8 0

3 years ago

Sibal started with $500 in a bank account that does not earn interest. In the middle of every month, she withdraws 1/5 of the ac

GalinKa [24]

4/5 of the original amount at the start of the month will remain. The amount at the start of every month will change. Thus:
an = 4/5 (an-1) ; where a1 = 500.

5 0

3 years ago

Holly and her 2 brst friends go to dinner. Their total bill is 31.84. They use a coupon for 15% off the total. If they split the

Tresset [83]

ANSWER:

$9.0.

Each person will owe $9.0.

STEP-BY-STEP SOLUTION:

Total amount of people:
= 3

Total bill:
= $31.84

Discount off total bill:
= 15%

Total bill after discount:
= 31.84 × ( 100% - 15% )
= 31.84 × 85%
= 27.064

Total bill after discount split evenly / Amount each person will owe:
= 27.064 ÷ 3
= 9.0213 ( 3 repeater )
= $9.0 ( rounded to the nearest tenth )

6 0

3 years ago

enot [183]

Answer:

D) 4.01 miles

Step-by-step explanation:

2.87 miles from Monday + 1.14 miles =4.01 ran on Tuesday

5 0

3 years ago

Read 2 more answers