A line is 180 degrees. Right? Okay.
Although there is a line between them, both angles will sum up to 180 degrees.
So the equation will be: 3x-20+x=180
You need to isolate the variable.
First add like terms: 3x+x=4x
So then the equation is 4x-20=180
After that you add 20 to both sides because the opposite of -20 is +20, and Denver what you do on one side needs to be reappeared to the other side
4x-20=180
+20 +20
4x= 200
Dived both by 4
4x=200
/4. /4
X=50
Angles:
X=50
3(50)-20=130(angle)
