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3 years ago

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The perimeter of an equilateral triangle is 6 cm more than the perimeter of a square. The length of a side of the square is 3 cm

less than the length of a side of the equilateral triangle. Find the area of the square.

1 answer:

yan [13]3 years ago

5 0

3t=4s+5 (s=side of square, t= side of triangle)

s=t-3, t=s+3, using this value for t in the first equation gives us:

3(s+3)=4s+5

3s+9=4s+5

-s=-4

s=4

so the side length of the square is 4cm and the area of a square is just s^2

A=16cm^2

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<u />

Center of mass is the point of gravity of an object if it is in an uniform gravitational field. For the lamina, or any other 2 dimensional object, center of mass is calculated by:

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$M_{y} = \int\limits^a_b {\int\limits^a_b {x.\rho(x,y)} \, dA }$

$M_{x}$ and $M_{y}$ are moments of the lamina about x-axis and y-axis, respectively.

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For moment about x-axis:

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