The teacher will be very surprised to see your correct solution 😉
(4*x - 3)*(4*x + 3) + -4*x + 1 = 3*x
a*x^2 + b*x + c = 0
D = b^2 - 4 * a * c =
(-7)^2 - 4 * (16) * (-8) = 561
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
_____ 7 \/ 561 x1 = -- - ------- 32 32
_____ 7 \/ 561 x2 = -- + ------- 32 32
x2 = 7/32 + sqrt(561)/32
sum
_____ _____ 7 \/ 561 7 \/ 561 -- - ------- + -- + ------- 32 32 32 32
=
7/16
product
/ _____\ / _____\ |7 \/ 561 | |7 \/ 561 | |-- - -------|*|-- + -------| \32 32 / \32 32 /
=
-1/2
-1/2