Given : ABCF is a Rectangle
⇒ AB = CF
Given : AB = 6 cm
⇒ CF = 6 cm
Perimeter of a Rectangle is given by : 2(Length + Width)
Given : Perimeter of the Rectangle = 20 cm
⇒ 2(6 + BC) = 20
⇒ 6 + BC = 10
⇒ BC = 4
Given : BD = 9
But, We can See that : BD = BC + CD
⇒ CD + 4 = 9
⇒ CD = 5
We know that :
✿ 
Where : a and b are Lengths of Parallel Sides and Height is Length between those Parallel Sides
In the Given Trapezium :
The Parallel Sides are CD and EF and Height is CF
Given : EF = 3 cm


Answer:
-9
Step-by-step explanation:
The in the first expression, y is to the -9'th degree, which means n is -9.
(If there are numbers of similar term multiplied together, the exponents are to be added.)
Step-by-step explanation:

1 ft = 12 inches
6 ft = 72 inches (multiply both sides by 6)
6 ft + 2 inches = 72+2 = 74 inches
6 ft, 2 inches = 74 inches
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1 ft = 12 inches
2 ft = 24 inches
2 ft + 1 in = 24+1 = 25 inches
2 ft, 1 in = 25 inches
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1 ft = 12 inches
3 ft = 36 inches
3 ft + 7 in = 36+7 = 43 inches
3 ft, 7 in = 43 inches
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To rewrite the problem a bit in equivalent form, we have a man who is 74 inches cast a shadow that is 25 inches long. The tree has a shadow of 43 inches. We want to find the height of the tree, which for now we'll call x
(tree height)/(tree shadow) = (person height)/(person shadow)
x/43 = 74/25
25x = 43*74
25x = 3182
x = 3182/25
x = 127.28 inches
The tree is 127.28 inches tall which is the same as 10 ft, 7.28 inches
because 127/12 = 10 remainder 7, then we add on the 0.28 portion