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As shown in the figure, in the rectangular coordinate system, calculate the coordinates of each vertex of the quadrilateral oabc, and calculate the area of the quadrilateral
Mm-hmm
In the plane rectangular coordinate system, the coordinates of each vertex of the quadrilateral oabc are o (0,0) a (14,0) B (12,8) C (4,10)
Find the perimeter and area of this quadrilateral?
Make AE ⊥ X axis to e, CF ⊥ X axis to F
Then s quadrilateral ABCD = s ⊿ OAE + s trapezoidal Cafe + s ⊿ BFC
=1/2*1*4+1/2*(4+6)*(4-1)+1/2*(6-4)*6
=2+15+6
=23
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