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3 years ago

4 + 2/7x = 8 what does x equal

2 answers:

8 0

Subtract 4 from both sides of the equation
you will end up with 2/7x=4
next multiply 7x by both sides
you will end up with 2=28x
next divide 28 from both sides
you will end up with x=1/14 in
fraction form. Hope this helps.

Eduardwww [97]3 years ago

5 0

4+2/7x=8
minus 4 from both sides
2/7x=4

now there are 2 paths possible
1. 2/(7x)=4, if so, go to AAAAAA
2. (2/7)x=4, if so, go to BBBBBB

AAAA
2/(7x)=4
times both sides by 7x
2=28x
divide both sides by 28
1/14=x

BBBBBBB
(2/7)x=4
times both sides by 7/2
x=28/2
x=14

x=1/14 or 14 depending on how the fraction is
1/14 if 2/(7x), 14 if (2/7)x

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Parallel to y = 3x − 2 and passes through (1, 4)

4vir4ik [10]

Answer:

y=3x + 1

Step-by-step explanation:

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3 years ago

Suppose that the weight (in pounds) of an airplane is a linear function of the total amount of fuel (in gallons) in its tahk. Wh

kvasek [131]

Answer:

2002 pounds

Explanation:

To know the weight of the plane, we need to find an equation that relates the amount of fuel to the weight.

This equation can be founded using the following

$y-y_1=m(x-x_1)$

Where m is the slope, x1 is the number of gallons and y1 is the respective weight. So, replacing m = 6.0, x1 = 51 gallons and y1 = 2206 pounds, we get:

$y-2206=6(x-51)$

Now, we can solve for y

$\begin{gathered} y-2206=6(x)-6(51) \\ y-2206=6x-306 \\ y=6x-306+2206 \\ y=6x+1900 \end{gathered}$

Then, we can calculate the weight of an airplane with 17 gallons of fuel replacing x = 17 on the equation above

y = 6x + 1900

y = 6(17) + 1900

y = 102 + 1900

y = 2002

Therefore, the answer is 2002 pounds

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1 year ago

20/256 Simplified. I need this answer. Will give brainliest

sasho [114]

Answer:

5/64

Step-by-step explanation:

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3 years ago

Read 2 more answers

Which function is the same as y = 3 cosine (2 (x startfraction pi over 2 endfraction)) minus 2? y = 3 sine (2 (x startfraction p

kirza4 [7]

The function which is same as the function y = 3cos(2(x +π/2)) -2 is: Option A: y= 3sin(2(x + π/4)) - 2

<h3>How to convert sine of an angle to some angle of cosine?</h3>

We can use the fact that:

$\sin(\theta) = \cos(\pi/2 - \theta)\\\sin(\theta + \pi/2) = -\cos(\theta)\\\cos(\theta + \pi/2) = \sin(\theta)$

to convert the sine to cosine.

<h3>Which trigonometric functions are positive in which quadrant?</h3>

In first quadrant (0 < θ < π/2), all six trigonometric functions are positive.
In second quadrant(π/2 < θ < π), only sin and cosec are positive.
In the third quadrant (π < θ < 3π/2), only tangent and cotangent are positive.
In fourth (3π/2 < θ < 2π = 0), only cos and sec are positive.

(this all positive negative refers to the fact that if you use given angle as input to these functions, then what sign will these functions will evaluate based on in which quadrant does the given angle lies.)

Here, the given function is:

$y= 3\cos(2(x + \pi/2)) - 2$

The options are:

$y= 3\sin(2(x + \pi/4)) - 2$
$y= -3\sin(2(x + \pi/4)) - 2$
$y= 3\cos(2(x + \pi/4)) - 2$
$y= -3\cos(2(x + \pi/2)) - 2$

Checking all the options one by one:

Option 1: $y= 3\sin(2(x + \pi/4)) - 2$

$y= 3\sin(2(x + \pi/4)) - 2\\y= 3\sin (2x + \pi/2) -2\\y = -3\cos(2x) -2\\y = 3\cos(2x + \pi) -2\\y = 3\cos(2(x+ \pi/2)) -2$

(the last second step was the use of the fact that cos flips its sign after pi radian increment in its input)
Thus, this option is same as the given function.

Option 2: $y= -3\sin(2(x + \pi/4)) - 2$

This option if would be true, then from option 1 and this option, we'd get:
$-3\sin(2(x + \pi/4)) - 2= -3\sin(2(x + \pi/4)) - 2\\2(3\sin(2(x + \pi/4))) = 0\\\sin(2(x + \pi/4) = 0$