Answer:
x= -28.173
Step-by-step explanation:
formula for quadratic equation, y= (-b±√(b²-4ac))/(2a)
a= 1, b= -4 and c= -1
y= 4 + √(16+4)
= 4 + √20
here,
sinx = y
sinx = 4+ √20
or, x= sin^-1 (4+√20)
which doesn't exist
taking
sinx = 4-√20
x = -28.173°
