Answers:
x = -8/5 or x = 8/5
Sum of the first ten terms where all terms are positive = 4092
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Explanation:
r = common ratio
- first term = 4
- second term = (first term)*(common ratio) = 4r
- third term = (second term)*(common ratio) = (4r)*r = 4r^2
The first three terms are: 4, 4r, 4r^2
We're given that the sequence is: 4, 5x, 16
Therefore, we have these two equations
Solve the second equation for r and you should find that r = -2 or r = 2 are the only possible solutions. If r = -2, then 5x = 4r solves to x = -8/5. If r = 2, then 5x = 4r solves to x = 8/5.
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To find the sum of the first n terms, we use this geometric series formula
Sn = a*(1 - r^n)/(1 - r)
We have
- a = 4 = first term
- r = 2, since we want all the terms to be positive
- n = 10 = number of terms to sum up
So,
Sn = a*(1 - r^n)/(1 - r)
S10 = 4*(1 - 2^10)/(1 - 2)
S10 = 4*(1 - 1024)/(-1)
S10 = 4*(-1023)/(-1)
S10 = 4092
Answer:
1763 ft²
Step-by-step explanation:
Using the given conversion factor, ...
(164 m²)(1 ft/(.305 m))² = 165/.093025 ft² ≈ 1763 ft²
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The exact conversion factor is 1/0.3048, so the area is closer to 1765 ft². For a 4-significant digit answer, you need to use a conversion factor accurate to 4 significant digits.
Step-by-step explanation:
The equation of a parabola with focus at (h, k) and the directrix y = p is given by the following formula:
(y - k)^2 = 4 * f * (x - h)
In this case, the focus is at the origin (0, 0) and the directrix is the line y = -1.3, so the equation representing the cross section of the reflector is:
y^2 = 4 * f * x
= 4 * (-1.3) * x
= -5.2x
The depth of the reflector is the distance from the vertex to the directrix. In this case, the vertex is at the origin, so the depth is simply the distance from the origin to the line y = -1.3. Since the directrix is a horizontal line, this distance is simply the absolute value of the y-coordinate of the line, which is 1.3 inches. Therefore, the depth of the reflector is approximately 1.3 inches.
Answer:
Part A : y²(x + 2)(x + 4)
Part B: (x + 4) (x + 4)
Part C: (x + 4) (x - 4)
Step-by-step explanation:
Part A: Factor x²y²+ 6xy²+ 8y²
x²y²+ 6xy²+ 8y²
y² is very common across the quadratic equation , hence
= y² (x² + 6x + 8)
= (y²) (x² + 6x + 8)
= (y²) (x² + 2x +4x + 8)
= (y²) (x² + 2x)+(4x + 8)
= (y²) (x(x + 2)+ 4(x + 2))
= y²(x+2)(x+4)
Part B: Factor x² + 8x + 16
x² + 8x + 16
= x² + 4x + 4x + 16
= (x² + 4x) + (4x + 16)
= x( x + 4) + 4(x + 4)
= (x + 4) (x + 4)
Part C: Factor x² − 16
= x² − 16
= x² + 0x − 16
= x² + 4x - 4x - 16
= (x² + 4x) - (4x - 16)
= x (x + 4) - 4(x + 4)
= (x + 4) (x - 4)
