Question

y sin² 63 +y sin² 27 ÷ 4 cos² 17 +4 cos² 73 = -1÷2​

Answer 1

ysin square 63+ y cos square 63 / 4 cos square 17 + 4 cos square 17 = -1/2

take common

y in numerator and 4 in denominator

you get

y/4 = -1/2

-4=2y

y= -2