Question 1034407
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The area of the triangle AOD is one fourth of the area of the parallelogram, which is 12*6 = 72 {{{cm^2}}}.


So the answer is {{{72/4}}} = 18 {{{cm^2}}}.


Why? Due to two reasons.


1. Because the diagonal of a parallelogram divides it in two congruent triangles, and 


2. Because the diagonals of a parallelogram bisect each other.



See the lessons 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Parallelograms/In-a-parallelogram-each-diagonal-divides-it-in-two-congruent-triangles.lesson>In a parallelogram, each diagonal divides it in two congruent triangles</A> 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Parallelograms/Properties-of-diagonals-of-parallelograms.lesson>Properties of diagonals of parallelograms</A> 

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