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3 years ago

Someone help me with this I will make you brain

Mathematics

1 answer:

hram777 [196]3 years ago

5 0

Step-by-step explanation:

let's look at the full numbers under the square roots when bringing the external factors back in :

sqrt(9×9×2) - sqrt(3×3×7) + sqrt(8) - sqrt(28)

and let's present these numbers as the product of their basic prime factors

sqrt(3×3×3×3×2) - sqrt(3×3×7) + sqrt(2×2×2) - sqrt(2×2×7)

now we see that we have 2 pairs of square roots : 1 pair ends with a factor of 2, and one pair with a factor of 7.

let's combine these

sqrt (3×3×3×3×2) + sqrt(2×2×2) - sqrt(3×3×7) - sqrt (2×2×7)

and now we move the factors of 2 and 7 back out in front (of course, we need to apply the square root on these factors) :

9×sqrt(2) + 2×sqrt(2) - 3×sqrt(7) - 2×sqrt(7) =

= (9+2)×sqrt(2) - (3+2)×sqrt(7) = 11×sqrt(2) - 5×sqrt(7)

and that is the first answer option.

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Solve for x in the equation x squared + 10 x + 12 = 36.

Anna35 [415]

It’s the first one

x = -12 or x=2

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3 years ago

Chaz is on a ladder 12 feet above ground.Chez is in the subway 15 feet underground. What is the distance from Chez to Chaz?

Vesna [10]

Answer:

27 feet

Step-by-step explanation:

4 0

3 years ago

How do I find x? I am not sure how to get it because of the lines

JulsSmile [24]

A triangle's angles will always equal up to 180. Since you already have to of the angles, you will add them up together. 30+20=50. Then, you take 180 and subtract it by the sum of the two previous angles. 180-50=130. Now you know the last angle is 130. You also know that the missing angle is also 130. The reason for that is because the two angles are the exact same if you look at it.

3 0

3 years ago

An object is heated to 100°. It is left to cool in a room that

stepladder [879]

Answer:

Step-by-step explanation:

Use Newton's Law of Cooling for this one. It involves natural logs and being able to solve equations that require natural logs. The formula is as follows:

$T(t)=T_{1}+(T_{0}-T_{1})e^{kt}$ where

T(t) is the temp at time t

T₁ is the enviornmental temp

T₀ is the initial temp

k is the cooling constant which is different for everything, and

t is the time (here, it's in minutes)

If we are looking first for the temp after 20 minutes, we have to solve for the k value. That's what we will do first, given the info that we have:

T(t) = 80

T₁ = 30

T₀ = 100

t = 5

k = ?

Filling in to solve for k:

$80=30+(100-30)e^{5k}$ which simplifies to

$50=70e^{5k}$ Divide both sides by 70 to get

$\frac{50}{70}=e^{5k}$ and take the natural log of both sides:

$ln(\frac{5}{7})=ln(e^{5k})$

Since you're learning logs, I'm assuming that you know that a natural log and Euler's number, e, "undo" each other (just like taking the square root of something squared). That gives us:

$-.3364722366=5k$

Divide both sides by 5 to get that

k = -.0672944473

Now that we have a value for k, we can sub that in to solve for T(20):

$T(20)=30+(100-30)e^{-.0672944473(20)}$ which simplifies to

$T(20)=30+70e^{-1.345888946}$

On your calculator, raise e to that power and multiply that number by 70:

T(20)= 30 + 70(.260308205) and

T(20) = 30 + 18.22157435 so

T(20) = 48.2°

Now we can use that k value to find out when (time) the temp of the object cools to 35°:

T(t) = 35

T₁ = 30

T₀ = 100

k = -.0672944473

t = ?

$35=30+100-30)e^{-.0672944473t}$ which simplifies to

$5=70e^{-.0672944473t}$

Now divide both sides by 70 and take the natural log of both sides:

$ln(\frac{5}{70})=ln(e^{-.0672944473t})$ which simplifies to

-2.63905733 = -.0672944473t

Divide to get

t = 39.2 minutes

3 0

4 years ago

Help me ASAP for this question

ivann1987 [24]

Answer: Y= 2x

Step-by-step explanation:

1 x 2 = 2

3.4 x 2 = 6.8

5 x 2 = 10

7 x 2 = 14

So. Y = 2x

4 0

3 years ago