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trapecia [35]
3 years ago
6

Solve this quadratic equation by completing the square.

Mathematics
1 answer:
nadya68 [22]3 years ago
3 0

Answer:

x=-3+\sqrt{27}\\  x=-3-\sqrt{27}

Step-by-step explanation:

Let's find our C value for the quadratic equation.

(\frac{6}{2})^{2} = 9

That is our C. Since we added 9 to one side, we have to do the same to the other. We get:

x^{2} +6x + 9 = 18 + 9\\x^{2} +6x + 9 = 27

Now, lets form the left side as a binomial squared.

(x+3)^{2} = 27

Let's square both sides now:

x+3 = (+/-)\sqrt{27}

Now, we subtract 3 from both sides to isolate the variable, X:

x= -3(+/-)\sqrt{27}

This means that the answers are:

x=-3+\sqrt{27}\\  x=-3-\sqrt{27}

I do not understand your answers though. Answer A makes no sense, answer B is 221, answer C is 115, and answer D also does not make sense. If you could clarify this portion, maybe I can help you find your alphabetic answer

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47% of $118 estimated
bezimeni [28]
1. We assume, that the number 118 is 100% - because it's the output value of the task. 
<span>2. We assume, that x is the value we are looking for. </span>
<span>3. If 118 is 100%, so we can write it down as 118=100%. </span>
<span>4. We know, that x is 47% of the output value, so we can write it down as x=47%. </span>
5. Now we have two simple equations:
1) 118=100%
2) x=47%
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
118/x=100%/47%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for what is 47% of 118

118/x=100/47
<span>(118/x)*x=(100/47)*x       - </span>we multiply both sides of the equation by x
<span>118=2.12765957447*x       - </span>we divide both sides of the equation by (2.12765957447) to get x
<span>118/2.12765957447=x </span>
<span>55.46=x </span>
x=55.46

<span>now we have: </span>
<span>47% of 118=55.46</span>
6 0
3 years ago
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Does the relationship in this table represent a proportional relationship? x 0.25 0.5 0.6 1.75 y 3.25 3.5 3.6 4.75 Select from t
ioda

Answer:

yes it does I had this question

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3 years ago
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Need help! Urgent help
Fed [463]

Answer:

1808.64 in²

Step-by-step explanation:

We can first convert 9 cm into 24 in using the scale. From there on outwards, we know that the area of a circle is equal to πr², so we just plug in 3.14 for π and 24 in for r. Then, we get 576(3.14) and finally 1808.64 in².

By the way, the scale is wrong. It should be 8 cm = 3 in, not 3 cm = 8 in.

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3 years ago
The formula for the perimeter of a rectangle is P=2(l+w).
olga2289 [7]

Answer:

See below.

Step-by-step explanation:

Part A.

I'm changing the l and w to capital letters, so you don't confuse the l (small-case L) with a 1 (one).

P =2(L + W)

Since W is on the right side, switch sides to end up with W on the left side.

2(L + W) = P

Since the quantity in parentheses is being multiplied by 2, we divide both sides by 2.

L + W = P/2

L is being added to W, so we subtract L from both sides.

W = P/2 - L

Part B.

First, I switched sides to have W on the left side. Then, I divided both sides by 2. Finally, I subtracted L from both sides.

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Solve a right triangle, find all angles and sides. ​
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Answer:

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Step-by-step explanation:

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