I don't know how to do it?
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Answer:
130°
Step-by-step explanation:
A hexagon's angels should be 720°.
so we need to substract the outer angels to find the interior angels.
180-75=105
180-38=142
180-42=138
180-65=115
180-90=90
then we add them up with x and equal it to 720
105+142+138+115+90+x=720
720-590=x
x=130
a=130
Answer:
a = 130°
Step-by-step explanation:
The interior angle of a polygon is calculated as
180° - exterior angle, thus
180° - 75° = 105°
180° - 42° = 138°
180° - 65° = 115°
180° - 90° = 90°
180° - 38° = 142°
The sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 6, thus
sum = 180° × 4 = 720°
Sum the interior angles and equate to 720
105 + 138 + 115 + 90 + 142 + a = 720, that is
590 + a = 720 ( subtract 590 from both sides )
a = 130