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The square root of the sum of twice a number and 3 is 6. find the number​

User DuckPuppy
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2 Answers

4 votes

Answer:


(33)/(2)

Explanation:

In the problem, "The square root of the sum of twice a number and 3 is 6" can be converted to an equation that looks like this:

Let x be the number:


√(2x+3 = 6 )

In order to solve the problem:


√(2x+3)^2=6^2

By squaring both sides to remove the exponent:


{2x + 3 = 36}

Simplify:


{2x+3-3=36-3}

Subtract 3 from both sides:


{2x = 33 }

Then Simplifying further:


(2x)/(2) = (33)/(2)

Divide both sides by 2 to remove 2 from the x.


{x = (33)/(2) }

Thus, meaning the answer is
(33)/(2)

Hope this helps you.

User Dckrooney
by
4.8k points
4 votes

Answer in fraction form = 33/2

Answer in decimal form = 16.5

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Work Shown:

n = some number

2n = twice that number

2n+3 = "sum of twice a number and 3"


√(2n+3) = square root of the previous expression

The equation we need to solve is
√(2n+3) = 6

We'll follow PEMDAS in reverse, undoing each operation, to isolate n


√(2n+3) = 6\\\\\left(√(2n+3)\right)^2 = 6^2 \ \ \text{ ... square both sides}\\\\2n+3 = 36\\\\2n+3-3 = 36-3 \ \ \text{ ... subtract 3 from both sides}\\\\2n = 33\\\\(2n)/(2)=(33)/(2) \ \ \text{ ... divide both sides by 2}\\\\n = (33)/(2)\\\\n = 16.5

User EricWasTaken
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4.2k points