The required area is 10.3 square units.
Area of triangle= 12 /(a* b)
Area of a triangle using trigonometric area formula = 1/2( a * b) sin(c)
here, base = a , height = b*sin(c)
Given ,
Only the sine of the included angle, whose two side lengths are specified, can be used despite the two angle measurements that have been provided. The EF and DF sides of our triangle's angle, which measures 31 degrees, are also provided.
On putting the values given in the formula we get,
Area = 1/2* 8 * 5sin(31)
= 20 * 0.51503807491
≈ 10.3
Therefore, the area of the triangle DEF is 10.3 square units.
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