What is the value of y in this equilateral triangle? (Brainly + Bonus points for the correct answer and best-explained answer)
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Answer:
y = 15
Step-by-step explanation:
this is an equilateral (therefore also equiangular) triangle
also known as a 60-60-60° triangle
each angle is 60° so you can set up this equation to solve for 'y'
5y - 15 = 60
5y = 75
y = 15