Answer:
m∠Y=50°
Step-by-step explanation:
So, we know that ∠S+∠Y=90 and that m∠S=2(m∠Y)-60.
If you plug those things into the equation, you get (2[m∠Y]-60)+m∠Y=90.
Then you multiply 2 and m∠Y: 2m∠Y-60+m∠Y=90.
Combine like terms: 3m∠Y-60=90.
Then you add 60 to both sides: 3m∠Y=150
Divide 3 on both sides: 3∠Y=50
