WORTH 50 POINTS PLEASE HELP MEEEE!!!!!!!
The numbers up and down there are both 10 degrees.
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40+10=50
180-50=130
10+20=30
180-30=15
angle at center add up to 360
360-(130+150)=80°
The triangle is an equilateral.
180-80=100
both base angles are 50°