Answer :
Option A is correct, the required simplified value of the x is given as 35.
In triangle DEF, if m∠D = (2x)°, m∠E = (2x − 4)°, and m∠F = (x + 9)°.
for the triangle sum of the interior angles is equal to 180°.
∠D + ∠E + ∠F = 180
2x + 2x - 4 + x + 9 = 180
5x + 5 = 180
5x = 175
x = 35
Thus, the required simplified value of the x is given as 35.
The sum of the measures of the interior angles of a triangle in Euclidean space is continually 180 stages. This reality is equal to Euclid's parallel postulate. This permits the determination of the degree of the 1/3 perspective of any triangle, given the measure of angles. An exterior perspective of a triangle is an attitude that is a linear pair (and subsequently supplementary) to an indoor angle.
The degree of an exterior perspective of a triangle is the same as the sum of the measures of the 2 indoor angles that aren't adjoining to it; this is the outside perspective theorem. The sum of the measures of the 3 exterior angles (one for every vertex) of any triangle is 360 degrees.
To learn more about interior angle visit here:
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