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3 years ago

Completing the Square

Mathematics

1 answer:

Softa [21]3 years ago

6 0

Answer:

C.7, -2

Step-by-step explanation:

A quadratic equation is a polynomial of degree two. A quadratic equation is in the form:

ax² + bx + c = 0; where a, b, c are constants.

Quadratic equation can be solved using different methods, such as completing the square method, quadratic formula.

Solving the equation 2x² - 10x - 20 = 8 using completing the square:

2x² - 10x - 20 = 8

2x² - 10x = 28

Divide through by 2, to make the coefficient of x² to be 1:

x² - 5x = 14

Add to both sides, the square of half of the coefficient of x [i.e. (-5/2)² = 6.25]

x² - 5x + 6.25 = 14 + 6.25

(x - 2.5)² = 20.25

taking square root of both sides:

x - 2.5 = √20.25

x - 2.5 = ±4.5

x = 2.5 ± 4.5

x = 2.5 + 4.5; or x = 2.5 - 4.5

x = 7 or x = -2

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Mrs Alivia’s bathroom is in the shape of a rectangle with a width of 6 feet. Her kitchen is in the shape of a rectangle with a w

Vedmedyk [2.9K]

Answer:

1. The length of the bathroom is equal to its width. FALSE

2. Equation 2(x+6)=29 can be used to find the length of the bathroom, x.

TRUE

3. The legend of the bathroom is 11.5 feet. FALSE

4. The equation 2 x+6=29 can be used to find the length of bathroom, x.

FALSE

5. The length of the bathroom is 8.5 feet. TRUE

Step-by-step explanation:

Here, given:

The width of the bathroom = 6 feet

The width of the kitchen = 10.75 ft

The perimeter of the bathroom = 29 feet

Let us assume the length of the bathroom = k units

PERIMETER OF A RECTANGLE = 2 ( LENGTH + WIDTH)

Now, for the Mrs Avila's bathroom

29 feet = 2 (k + 6)

⇒ 29 = 2k + 12

or, 2 k = 29 - 12 = 17

⇒ k = 17/2 = 8.5 feet

So, the length of the bathroom = 8.5 units

Now, let us consider the given statements:

1. The length of the bathroom is equal to its width. FALSE

As here, Length= 8.5 units and width = 6 units

2. Equation 2(x+6)=29 can be used to find the length of the bathroom, x.

TRUE

3. The legend of the bathroom is 11.5 feet.

FALSE, the length of the bathroom is 8.5 units.

4. The equation 2 x+6=29 can be used to find the length of bathroom, x.

FALSE, the correct equation that can be used is 2x + 12 = 29

5. The length of the bathroom is 8.5 feet.

TRUE

5 0

3 years ago

You use the compass to draw a circle. What will be the area of the circle?

Greeley [361]

Answer:

are there any answer choices

Step-by-step explanation:

i believe its 18

sry if im wrong

8 0

3 years ago

Is 0.75 greater than 0.100?

Naya [18.7K]

Yes because you only need to look at the first decimal for problems like these and the first number you see a seven and a one and seven is greater than one

8 0

3 years ago

Solve the following problem. Give the equation using x as the variable, and give the answer.

Vinil7 [7]

Answer:

A. 3x + (x+8) = -22 - 2x

Step-by-step explanation:

Let the number equal x.

Set up the first half of the equation.

The sum of three times the number and 8 more than the number can be written as:

3x + (x+8)

Sum means that you add the components.

Set up the second half of the equation.

The difference between -22 and twice the number can be written as:

-22 - 2x

Difference means subtraction, and because -22 is written first, that is the number that you subtract <em>from</em>.

If you set the halves of the equation equal, you get:

3x + (x+8) = -22 - 2x

Therefore, the answer is A.

5 0

2 years ago

Find the probability of exactly three successes in six trials of a binomial experiment in which the the probability of is 50%.

Lyrx [107]

Start by doing the binomial expansion of (x+y)^6 where x represents success. This is

(x^6y^0) + 6(x^5y^1) +15(x^4y^2) +20(x^3y^3) +15(x^2y^4) +6(x^1y^5) +(x^0y^6)

We are interested in the x^3y^3 term which represents exactly 3 sucesses. Since the probalbility of sucess and failure are both .5 we should be able to figure this out just using the coefficients of the terms which is

20/64 = .3125 which is 31.25%

4 0

3 years ago