H (x) = 4x2 + 12x + 8

x=-1

x=-2

Step-by-step explanation:

4x2 + 12x + 8

To solve a quadratic equation, factorisation Method, formulae method or completing the square method can be used. But for the purpose of this question, the formulae method will be used.

(-b±√ (b²-4ac)) 2a

Where a=4, b=12 and c=8

(-12±√ (12²-4 (4) (8)) / 2 (4)

(-12±√ (144-128) / 8

(-12±√16) / 8

(-12±4) / 8

(-12+4) / 8 or (-12-4) / 8

-8/8 or - 16/8

-1 or - 2