Respuesta :
The sum of all the angles of a triangle is equal to 180°. The value of x is 12.
What is the sum of all the angles of a triangle?
The sum of all the angles of a triangle is equal to 180°.
What is the exterior angle?
The Exterior Angle is the angle formed by either of a shape's sides and a line drawn from the opposite side.
We know that in a triangle the sum of the exterior angle and the interior angle is 180°. Therefore, the following angles of the triangle can be written as,
[tex]\angle H=180-(9x+6)[/tex]
[tex]\angle G=180-(10x-1)[/tex]
[tex]\angle J=180-(10x+7)[/tex]
Now, the sum of all the angles of the triangle is 180°, therefore, the sum can be written as,
[tex]\angle H+\angle G+\angle J=180^o\\\\180-(9x+6) + 180-(10x-1) + 180-(10x+7) = 180\\\\540-(9x+6)-(10x-1)-(10x+7)=180\\\\540-180 = (9x+6)+(10x-1)+(10x+7)\\\\360=9x+6+10x-1+10x+7\\\\360=29x+12\\\\360-12=27x\\\\x = 12[/tex]
Hence, the value of x is 12.
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