If the quadratic formula is used to solve 2x(x + 5) = 4, what are the solutions? {-1/2, -9/2}

x²+bx=c
x=[-b+√(b²+4c)]/2

2x(x+5)=4
2x²+10x=4
x²+5x=2

x=[-5+√(5²+4*4)]/2 

if b=-1/2 and c=-9/2
x= {1/2+√[(1/2)²+4*(-9/2)]}/2