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3 years ago

Solve x^(2)+4x=4 for x by completing the square.

Mathematics

1 answer:

Mama L [17]3 years ago

8 0

Answer:

x = 2 sqrt(2) - 2 or x = -2 - 2 sqrt(2)

Step-by-step explanation:

Solve for x:

x^2 + 4 x = 4

Add 4 to both sides:

x^2 + 4 x + 4 = 8

Write the left hand side as a square:

(x + 2)^2 = 8

Take the square root of both sides:

x + 2 = 2 sqrt(2) or x + 2 = -2 sqrt(2)

Subtract 2 from both sides:

x = 2 sqrt(2) - 2 or x + 2 = -2 sqrt(2)

Subtract 2 from both sides:

Answer: x = 2 sqrt(2) - 2 or x = -2 - 2 sqrt(2)

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spin [16.1K]

B because 14-5=9 and 9-8= 1

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3 years ago

How do you get this answer ?

Leno4ka [110]

If you
Let x to be the total number of pages in a book,

then 1/3x = 117

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3 years ago

If f(x)=3x+2, find the following value:<br> f(4)=?

lubasha [3.4K]

Answer:

f(4)=14

Step-by-step explanation:

f(x)=3x+2

f(4)=3x+2

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Hope this helps!

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3 years ago

Devon made a box with length x+1, width x+3, and height x-3. What is the volume of Devon's box as a function of x?

erica [24]

Answer:

(a)

$V=x^3+x^2-9x-9$

(b)

$x=10$

(c)

$x=\frac{7}{2}$

Step-by-step explanation:

we are given

length is x+1

$L=x+1$

width is x+3

$W=x+3$

height is x-3

$H=x-3$

(a)

we can use volume formula

$V=L\times W\times H$

now, we can plug it

$V=(x+1)\times (x+3)\times (x-3)$

now, we can simplify it

$V=x^3+x^2-9x-9$

(b)

we are given volume =1001

so, we can set V=1001

and then we can solve for x

$V=x^3+x^2-9x-9=1001$

now, we can factor it

$\left(x-10\right)\left(x^2+11x+101\right)=0$

$x-10=0$

$x=10$

(b)

we are given volume

so, we can set

$V=14\frac{5}{8}=\frac{14\times 8+5}{8}$

$V=\frac{117}{8}$

and then we can solve for x

$V=x^3+x^2-9x-9=\frac{117}{8}$

now, we can factor it

$8x^3+8x^2-72x-189=0$

$\left(2x-7\right)\left(4x^2+18x+27\right)=0$

$2x-7=0$

$x=\frac{7}{2}$

8 0

3 years ago

If I could get some help it would be very much appreciated

raketka [301]

Answer:

Step-by-step explanation:

A circle is 360 degrees. What we are asked in words is, "How many degrees is 40% of 360?" Let x be "how many degrees"; the word "is" means =; 40% as a decimal is .4; the word of in this context means to multiply; and 360 is just 360. Putting all that together into an equation we can solve for x:

x = .4(360) so

x = 144

Adventure movies covers 144 degrees of that circle.

5 0

3 years ago

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