Answer:
Pythagorean Theorem: c2 = a2 + b2
Find the area by adding the areas of the three triangles. The area of a right triangle is: A = ½bh
Two triangles are identical so you can just multiply the area of the first triangle by two: 2A1 = 2(½bh) = 2(½ab) = ab.
The total area of the trapezoid is : A1 + A2 = ab + ½c2
You multiply both sides by 2 to get rid of the ½: (a2 + 2ab + b2) = 2ab + c2
You subtract out the 2ab: a2 + b2 = c2.
Then what is left is the proof: a2 + b2 = c2
x = 2(180 - x) - 12
3x = 348
x = 116
The measure of the angle is 116 degrees.
Step-by-step explanation:
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5:
1/2 , 3/5 , .606 , 13/20 , 66%
6:
0.09 , 1/10 , 12% , .13 , 3/20