jugoslav

A = (12 * 8) + (3 * 6) / 2 

A = [sqrt(2 * 6²) / 2]² *pi - 6²/ 2

The area of the outer square is  5² = 25 cm² 

The area of the blue square is    3.8² = 14.44 cm²

The area of a triangle is   (25 - 14.44) / 4 = 2.64 cm²

The height (h) of a triangle       h = (2 * 2.64) / 3.8

                                                  h = 1.389473684 cm    

Circle radius   r = 2√5

The length of a side of the square is  2(2√5)

Area of the square = [2(2√5)]² units squared

I got 26 points 

1/  All sides of the rhombus are equal.

2/  The opposite sides of a rhombus are parallel.

3/  Opposite angles of a rhombus are equal.

4/  In a rhombus, diagonals bisect each other at right angles.

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Side  a = 160 / 4 = 40

1/2 of the diagonal is  30 / 2 = 15

sqrt(40² - 15²) =  √1375

A = 2( 15 * √1375 )

5x - 4 = 3x + 10

2x = 14

x = 7

4x - 5 = 23

A = 23²*pi       or     529pi

Hint:    x = 28 / (3 + 5 + 6) 

XU = 4        UV = 6        VY = 8

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XV * VY = GV * VH = 80

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XU * UY = EU * UF = 56

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XY = 18 units