Answer:
The value of (f+g)(x) is x^2 + 3x - 11
You can combine this by simply adding the like terms. Start by adding together all of the x^2 terms. Since only g(x) has one of those, we use that in its entirety.
x^2
Next we add together the x terms. f(x) has 7x and g(x) has -4x.
7x + -4x = 3x
Finally, we add together the constants. f(x) has -3 and g(x) has -8.
-3 + -8 = -11
With all of the like terms combined, we simply take the answers and put them together.
x^2 + 3x - 11
Explanation: