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3 years ago

If x=7+root 40 ,find the value of root x+1by the root of x

Mathematics

1 answer:

Luda [366]3 years ago

3 0

Chapter : Algebra

Study : Math in Junior high school

x = 7 + √40

find √x of √x + 1

= √x + 1

= √(7+√40) + 1

in Formula is :

= √7+√40 = √x + √y

= (√7+√40)² = (√x + √y)²

= 7+√40 = x + 2√xy + y

= 7 + √40 = x + y + 2√xy

→ 7 = x + y → y = 7 - x ... Equation 1

→ √40 = 2√xy → √40 = 2.2√10 = 4√10

= xy = 10 ... Equation 2

substitution Equation 1 to 2 :

= xy = 10

= x(7-x) = 10

= 7x - x² = 10

= x² - 7x + 10 = 0

= (x - 5)(x - 2) = 0

= x = 5 or x = 2

Subsitution x = 5 and x = 2, to equation 1

#For x = 5

= y = 7 - x

= y = 7 - (5)

= y = 2

#For x = 2

= y = 7 - x

= y = 7 - (2)

= y = 5

and his x and y was find :

#Equation 1 :

= x = 5 and y = 2

#Equation 2 :

= x = 2 and y = 5

So that :

√7+√40 = √x + √y

= √7+√40 = √2 + √5

And that is answer of question :

= √2 + √5 + 1

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Step-by-step explanation:

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or, 2 y + 5 z = 15

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Step-by-step explanation:

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Step-by-step explanation:

We are given that the time taken by a randomly selected applicant for a mortgage to fill out a certain form has a normal probability distribution with average time 10 minutes and a standard deviation of 2 minutes.

Also, five individuals fill out the form on Day 1 and six individuals fill out the form on Day 2.

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The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean time = 10 minutes

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Now, the probability that the sample average time taken is less than 11 minutes for Day 1 is given by = P( $\bar X$ < 11 minutes)

P( $\bar X$ < 11 minutes) = P( $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ < $\frac{11-10}{\frac{2}{\sqrt{5} } }$ ) = P(Z < 1.12) = 0.86864

The above probability is calculated by looking at the value of x = 1.12 in the z table which has an area of 0.86864.

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The z score probability distribution for sample mean is given by;

Z = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }$ ~ N(0,1)

where, $\mu$ = population mean time = 10 minutes

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n = sample of individuals fill out form on Day 2 = 6

Now, the probability that the sample average time taken is less than 11 minutes for Day 2 is given by = P( $\bar X$ < 11 minutes)

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The above probability is calculated by looking at the value of x = 1.22 in the z table which has an area of 0.88877.

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If x=7+root 40 ,find the value of root x+1by the root of x​

If x=7+root 40 ,find the value of root x+1by the root of x