Mathematics, 21.07.2019 08:00 tifftiff22

20 pts hurrya blackboard has an area of 28ft2 and a perimeter of 22 ft. what are the dimensions of the board?

Answers: 2

Show answers

Answers

Answer from: Admin

2[L + W] =22

L*W = 28

W = 28/L sub this in the first equation

Solve for L:

2 (L + 28/L) = 22

Divide both sides by a constant to simplify the equation.

Divide both sides by 2:

L + 28/L = 11

Write the left hand side as a single fraction.

Bring L + 28/L together using the common denominator L:

(L^2 + 28)/L = 11

Multiply both sides by a polynomial to clear fractions.

Multiply both sides by L:

L^2 + 28 = 11 L

Move everything to the left hand side.

Subtract 11 L from both sides:

L^2 - 11 L + 28 = 0

Factor the left hand side.

The left hand side factors into a product with two terms:

(L - 7) (L - 4) = 0

Find the roots of each term in the product separately.

Split into two equations:

L - 7 = 0 or L - 4 = 0

Look at the first equation: Solve for L.

Add 7 to both sides:

L = 7 or L - 4 = 0

Look at the second equation: Solve for L.

Add 4 to both sides:

L = 7 or L = 4 and W=4 or W = 7

Answer from: ladybugys

2[L + W] =22

L*W = 28

W = 28/L sub this in the first equation

Solve for L:

2 (L + 28/L) = 22

Divide both sides by a constant to simplify the equation.

Divide both sides by 2:

L + 28/L = 11

Write the left hand side as a single fraction.

Bring L + 28/L together using the common denominator L:

(L^2 + 28)/L = 11

Multiply both sides by a polynomial to clear fractions.

Multiply both sides by L:

L^2 + 28 = 11 L

Move everything to the left hand side.

Subtract 11 L from both sides:

L^2 - 11 L + 28 = 0

Factor the left hand side.

The left hand side factors into a product with two terms:

(L - 7) (L - 4) = 0

Find the roots of each term in the product separately.

Split into two equations:

L - 7 = 0 or L - 4 = 0

Look at the first equation: Solve for L.

Add 7 to both sides:

L = 7 or L - 4 = 0

Look at the second equation: Solve for L.

Add 4 to both sides:

L = 7 or L = 4 and W=4

Answer from: Quest

Bbbhkkk

Answer from: Quest

Hey mate where is the graph

Other questions on the subject: Mathematics

Mathematics, 21.06.2019 16:30, pedro48

Read the following two statements. then use the law of syllogism to draw a conclusion. if the tv is too loud, then it will give me a headache. if i have a headache, then i will have to rest.

Answers: 2

continue

Mathematics, 21.06.2019 17:30, neverfnmind

James adds two numbers a + b. sally adds the same two numbers but reverse the order b + a what property of addition assures us that james and sally will get the same sum

Answers: 2

continue

Mathematics, 21.06.2019 19:00, cheryljoseph69

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a. m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

Answers: 3

continue

Mathematics, 21.06.2019 19:00, ale1910

Quick! a survey of 57 customers was taken at a bookstore regarding the types of books purchased. the survey found that 33 customers purchased mysteries, 25 purchased science fiction, 18 purchased romance novels, 12 purchased mysteries and science fiction, 9 purchased mysteries and romance novels, 6 purchased science fiction and romance novels, and 2 purchased all three types of books. a) how many of the customers surveyed purchased only mysteries? b) how many purchased mysteries and science fiction, but not romance novels? c) how many purchased mysteries or science fiction? d) how many purchased mysteries or science fiction, but not romance novels? e) how many purchased exactly two types of books?

Answers: 3

continue

You know the right answer?

20 pts hurrya blackboard has an area of 28ft2 and a perimeter of 22 ft. what are the dimensions of t...