How would I do this? What would it be?
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Answer: [tex]x=80[/tex]
Step-by-step explanation:
By definition, the sum of the exterior angles of a polygon is 360 degrees.
Knowing this, you can write the following equation:
[tex](x+8)+(2x+12)+(x+20)=360[/tex]
Then, you must solve for "x" in order to find its value. To do it, you can follow these steps:
1. You need to add the like terms:
[tex](x+8)+(2x+12)+(x+20)=360\\\\4x+40=360[/tex]
2. Now, subtract 40 from both sides of the equation:
[tex]4x+40-(40)=360-(40)\\\\4x=320[/tex]
3. Finally, you must divide both sides of the equation by 4. Then:
[tex]\frac{4x}{4}=\frac{320}{4}\\\\x=80[/tex]