+128631 Let the roots be a , b
By Vieta....the sum of the roots - (-3) / 1 = 3
And the product of the roots = 7/1 = 7
So
a + b = 3 square both sides ⇒ a^2 + 2ab + b^2 = 9 (1)
And
ab = 7 (2)
sub (2) into 1
a^2 + 2 (7) + b^2 = 9
a^2 + b^2 + 14 = 9
a^2 + b^2 = -5 square both sides again
a^4 + 2a^2b^2 + b^4 = 25
a^4 + b^4 + 2(ab)^2 = 25
a^4 + b^4 + 2(7)^2 = 25
a^4 + b^4 + 98 = 25
a^4 + b^4 = -73
