Answer:
c
Step-by-step explanation:
if I understand this right, then the expression is
2×sqrt(28) - 5×sqrt(63)
let's look for squared factors in the numbers under the square roots.
28 = 4×7 (4 is a squared number)
63 = 9×7 (9 is a squared number)
so,
2×sqrt(4×7) - 5×sqrt(9×7) =
= 2×2×sqrt(7) - 5×3×sqrt(7) = 4×sqrt(7) - 15×sqrt(7) =
= (4 - 15)×sqrt(7) = -11×sqrt(7)
The number of feet in the length of the handrail is 17.3 ft.
The easiest way to see this is to imagine that we can "unfold" the spiral to create a rectangle
The bottom side of the rectangle is just the arc length of a circle with a radius of 3 ft turned through 270°= (3/4) of a whole revolution
(3/4) (2pi) (3) = (9/2)pi ft = 4.5 pi ft
The side of the rectangle will be the rise of the staircase = 10ft
And the diagonal of the rectangle will be the length of the handrail
We can use the Pythagorean Theorem to solve this
Handrail length = √ [ (4.5 pi)^2 + 10^2 ] ≈ 17.3 ft
Pythagorean theorem is the well-known geometric theorem that the sum of the squares on the legs of a right triangle is equal to the square on the hypotenuse.
Learn more about the Pythagorean theorem here: brainly.com/question/343682
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Answer:
The answer is 2.
Step-by-step explanation:
Given: - 6 - (-6) + 7 + ( - 4) + ( - 1)
= - 6 + 6 + 7 - 4 - 1
= 6 + 7 - 6 - 4 - 1
= (6 + 7) - (6 + 4 + 1)
= 13 - 11
= 2
Hence, the answer.
I think it is yz but I and not completely sure