SOLUTION: The trapezoid shown is divided into four triangles by its diagonals. The area of two triangles are indicated(9 and 25). What is the area of the whole trapezoid?
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-> SOLUTION: The trapezoid shown is divided into four triangles by its diagonals. The area of two triangles are indicated(9 and 25). What is the area of the whole trapezoid?
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Question 1195835: The trapezoid shown is divided into four triangles by its diagonals. The area of two triangles are indicated(9 and 25). What is the area of the whole trapezoid?
Let "a" be the shorter base of the trapezoid;
let "b" be the longer base of the trapezoid.
The triangles of the areas 9 and 25 square units are similar,
with the similarity coefficient of (smaller to larger).
Let h be the height of the smaller triangle drawn to its base "a";
Let H be the height of the larger triangle drawn to its base "b".
Then from the similarity of triangles, b = ; H = .
We have then = = = ;
h + H = = .
The area of the trapezoid is
Area = = = ;
but = the area of the upper triangle = 9; hence ah = 2*9; therefore
Area = = 32*2 = 64 square units.
ANSWER. The area of the trapezoid is 64 square units.