The teacher will be very surprised to see your correct solution 😉
a*x^2 + b*x + c = 0
D = b^2 - 4 * a * c =
(-7)^2 - 4 * (1) * (3) = 37
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
____ 7 \/ 37 x1 = - - ------ 2 2
____ 7 \/ 37 x2 = - + ------ 2 2
x2 = sqrt(37)/2 + 7/2
sum
____ ____ 7 \/ 37 7 \/ 37 - - ------ + - + ------ 2 2 2 2
=
7
product
/ ____\ / ____\ |7 \/ 37 | |7 \/ 37 | |- - ------|*|- + ------| \2 2 / \2 2 /
=
3
3