-Notice that dividing our numbers leaves no remainder:
1,620 ÷ 5 = 324 + 0
-1,620 has all the factors of the number 5
Trinomial is the ancer to the first one
Where's the problem or the work ?
Look at the picture.
The area of the hexagon is equal six times the area of the <span>equilateral triangle.
The formula of the </span><span>equilateral triangle with the leg
a:

Therefore the formula of the area of the hexagon with a side lenght
a is:

We have
a = 12cm. Substitute:

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