help me with angle sum theorem please what is y
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Answer:
y = 140
Step-by-step explanation:
All angles inside the triangle will equal 180
Set your formula up as
180 = x + 120 + 20
180 - 120 - 20 = x
40 = x
y+x will also equal 180, therefore
180 = y + x
180 = y + 40
180 - 40 = y
140 = y