Answer: The required value of x is - 2.
Step-by-step explanation: We are given the following two functions :
![f(x)=x^2-2x,~~~~~g(x)=6x+4.](https://img.qammunity.org/2019/formulas/mathematics/middle-school/41w13bb31visfjvyoxi421dejtznb5lzkv.png)
We are to find the value of x for which (f + g)(x) = 0.
We know that for any two functions p(x) and q(x), the following property holds true :
![(p+q)(x)=p(x)+q(x).](https://img.qammunity.org/2019/formulas/mathematics/high-school/abbu8vmq08hlkjm8itmplu8wy7ywfoek5t.png)
We have
![(f+g)(x)=0\\\\\Rightarrow f(x)+g(x)=0\\\\\Rightarrow x^2-2x+6x+4=0\\\\\Rightarrow x^2+4x+4=0\\\\\Rightarrow (x+2)^2=0\\\\\Rightarrow x+2=0,~~~x+2=0\\\\\Rightarrow x=-2,~-2.](https://img.qammunity.org/2019/formulas/mathematics/middle-school/hgixl5o04pihtgpo63g6njxt3yx7h6hc7v.png)
Thus, the required value of x is - 2.