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3 years ago

How do you work out this problem using completing the square x2 - 4x - 80 = 0

Mathematics

2 answers:

Ugo [173]3 years ago

7 0

x^2 - 4x = 80

x^2 - 4x + 4 = 80 + 4 (Divide b, which is 4, by 2 and square it.)

x^2 - 4x + 4 = 84

sqrt(x + 2)^2 = sqrt(84)

x + 2 = plus or minus sqrt(84)

Subtract 2 from both sides

x = -2 plus or minus sqrt(84)

yulyashka [42]3 years ago

3 0

Answer:

A value that satisfies this equation is called a root, zero or solution of the equation!! We have three ... Solve each by factoring. 1) x2 + 4x -5 = 0 ... Follow the explanation and sample problem to review completing the square.

Step-by-step explanation:

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Use circle C classify arc MNO in circle C

inna [77]

Answer:

Semicircle

Step-by-step explanation:

As we can see, the arc is bounded by the chord MO

since the chord passes through the center of the circle, we have it that the chord is a diameter

Mathematically, an arc bounded by a diameter represents half of a circle

So we can conclude that the arc MNO in circle C is a semicircle

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2 years ago

A pharmacist has 80 milileters of a 25 percent saline solution. Which expression can be used to find the percentage of the conce

Thepotemich [5.8K]

Answer:

Step-by-step explanation:

Final concentration % = [grams of salt / mililiters of solution] * 100

grams of salt = grams of salt from solution 1 + grams of salt from solution 2

grams of salt from solution 1 = mililiters * %/100 = 80 mililiters * 0.25 g/mililiters = 20 g

grams of salt from solution 2 = mililiters *%/100 = x*0.10 g/mililiters = 0.1x

mililiters of final solution = mililiters from solution 1 + mililiters from solution 2

mililiters of final solution = 80 mililiters + x mililiters

=> Final concentration, % = [0,10x + 20 g] / [x + 80 mililiters] * 100

6 0

3 years ago

Write a paragraph explaining how Theoderic’s actions after becoming king of Italy weakened the idea of Roman greatness. NEED DON

Irina18 [472]

After resuming as the leader of the Ostrogoths, Theodoric in 493 killed his brother became Lord of the land, and refused to submit Italy to the Roman Emperor. According to history, it made no sense to him to continue to submit to an emperor in Rome that was far away and who didn't have any interest in Italy but to siphon it.

<h3>Who was Theodoric?</h3>

Also known as Theodoric the Great, or as Flavius Theodoricus, he was the King of the Ostrogoths.

Under the direction of the Roman Emperor - Zeno, he has invaded Italy and removed the incumbent King - Odoacer.

See the link below for more about Theodoric:

brainly.com/question/19569498

6 0

2 years ago

The amount of gasoline sold each month to customers at Bob's Exxon station in downtown Navasota is a random variable. This rando

swat32

Answer:

The probability that Bob will win that wonderful trip on the basis of his gasoline sales this month

P(X≥ 2800) = P(Z₁≥1.5) = 0.0768

Step-by-step explanation:

Step(i):-

Mean of the Population (μ) = 2500 gallons

Standard deviation of the population (σ) =200 gallons

Let 'X' be a random variable in Normal distribution

Given X = 2800

$Z = \frac{x-mean}{S.D} = \frac{2800-2500}{200} = 1.5$

Step(ii):-

The probability that Bob will win that wonderful trip on the basis of his gasoline sales this month

P(X≥ 2800) = P(Z₁≥1.5)

= 0.5 - A(Z₁)

= 0.5 - A(1.5)

= 0.5 -0.4232 ( from normal table)

= 0.0768

Conclusion:-

The probability that Bob will win that wonderful trip on the basis of his gasoline sales this month

P(X≥ 2800) = P(Z₁≥1.5) = 0.0768

3 0

2 years ago

Find the 6th term of the arthemetic sequence 2x+3,-2x+10,-6x+17,..

sveticcg [70]

Answer:4h term: -10x+24, 5th term: -14x+31, 6th term: -18x+ 38

Step-by-step explanation:

8 0

2 years ago