Answer:
n = 5
Step-by-step explanation:
- Move all terms not containing n to the right side of the equation.
7n = 31 + 4
7n = 35
- Divide each term by 7 and simplify.
n = 5
i hope this helps :)
Answer: Choice C) 124 square cm
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Explanation:
Let's calculate the area of the trapezoid shown
b1 and b2 are the parallel bases; h is the height of the 2D trapezoid
b1 = 2
b2 = 5
h = 1.5
A = h*(b1+b2)/2
A = 1.5*(2+5)/2
A = 1.5*7/2
A = 10.5/2
A = 5.25
The area of one 2D trapezoid is 5.25 sq cm
There are two of these trapezoids that form the base faces of the trapezoidal prism. So the total base area is 2*5.25 = 10.5 sq cm
Keep this value (10.5) in mind. We'll use it later.
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Now onto the lateral surface area (LSA)
It turns out that the formula for the LSA is
LSA = p*d
where
p = perimeter of the trapezoid shown
d = depth or height of the 3D trapezoid (I'm not using h as it was used earlier)
This formula works for any polygonal base. It doesn't have to be a trapezoid.
In this case the perimeter is,
p = 1.7+2+2.65+5
p = 11.35
So
LSA = p*d
LSA = 11.35*10
LSA = 113.5
Add this LSA to the base area found earlier
10.5+113.5 = 124
The total surface area is 124 square cm
Answer:
326
Step-by-step explanation:
First you find the area of the triangles. Since squares have equal sides we know that the triangle has a side of 20 and 12. We plug this information into the formula A=20x12/2 which equal 120 but since we have 2 triangles we multiply by 2 and get 240. Then we find the area of the square which is 400 when you multiply 20x20. Then you find the area of the circle which is 3.14x10^2 which equals 314. You add 240 and 400 to get 640. You subtract 460 from 314 and get 326.
Answer:
Theoretically, about 208 times, but it doesn't work in practice
