Answer:
- x = -1/2(1 +√21) ≈ -2.79129
- x = -1/2(1 -√21) ≈ 1.79129
Step-by-step explanation:
We assume the middle term is supposed to be 4x.
We can remove a common factor of 4 to simplify this a bit.
x^2 +x -5 = 0
This is of the form
ax^2 +bx +c = 0
where a=1, b=1, c=-5.
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The <em>quadratic formula</em> gives the solutions as ...
Filling in the given coefficients, we have ...
x = (-1 ±√(1^2 -4·1·(-5)))/(2·1)
x = (-1±√21)/2
The solutions are x = -1/2(1 +√21) and -1/2(1 -√21).
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<em>If what you wrote is what you intend</em>, then the equation simplifies to 4x^2 -16 = 0.
Dividing by 4 and factoring the difference of squares gives ...
x^2 -4 = 0
(x -2)(x +2) = 0
These factors are zero (hence their product is 0) for the values x = 2 and x = -2.
The solutions are x=2 and x=-2.
Answer:
-12
Step-by-step explanation:
We start with the equation: 
Substitute the variables: 
Solve using order of operations (start with multiplication): 
And then addition/subtration: 
Answer:
3.74 x 10^5
Step-by-step explanation:
First expand the term in scientific notation into normal notation.
3.3 x 10^5 - Here the ^5 tells us to move the decimal five places to the right, so we go from
3.30000 to
330000.00
So 3.3 x 10^5 = 330,000
Now add that to 44,000 and you get 374,000.
Return this number to scientific notation. Move the decimal back to its spot before the 3. We go from
374,000.00 to
3.74000
Once again the decimal has moved five places, so that is the number in the exponent of the our scientific notation, and therefore our answer is
3.74 x 10^5
Answer:
a) cos(α+β) ≈ 0.8784
b) sin(β -α) ≈ -0.2724
Step-by-step explanation:
There are a couple of ways to go at these. One is to use the sum and difference formulas for the cosine and sine functions. To do that, you need to find the sine for the angle whose cosine is given, and vice versa.
Another approach is to use the inverse trig functions to find the angles α and β, then combine those angles and find find the desired function of the combination.
For the first problem, we'll do it the first way:
sin(α) = √(1 -cos²(α)) = √(1 -.926²) = √0.142524 ≈ 0.377524
cos(β) = √(1 -sin²(β)) = √(1 -.111²) ≈ 0.993820
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a) cos(α+β) = cos(α)cos(β) -sin(α)sin(β)
= 0.926×0.993820 -0.377524×0.111
cos(α+β) ≈ 0.8784
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b) sin(β -α) = sin(arcsin(0.111) -arccos(0.926)) ≈ sin(6.3730° -22.1804°)
= sin(-15.8074°)
sin(β -α) ≈ -0.2724
1) we calculate the volume of the first carton:
volume=length x width x height
volume=3 ft * 2 ft * 2 ft=12 ft³
Therefore:
A machine can fill 12 ft³ in 3 seconds.
2) we calculate the volume of the second carton.
volume=length x width x heigth
volume=4 ft * 5 ft * 6 ft=120 ft³
3) we calculate the time that the machine needs for fill the second carton with packing material by the rule of three.
12 ft³---------------------3 seconds
120 ft³-------------------- x
x=(120 ft³ * 3 seconds) / 12 ft³=30 seconds.
answer: 30 seconds.
