I've tried this problem like 7 times and still struggling:

f(x)=9x^3+2x^2-5x+4
and g(x)=5x^3-7x+4
so what is f(x)-g(x)? My answer was 4x^3+2x^2+2x...... is this correct? If not please help.

f(x)-g(x)

= 9x^3+2x^2-5x+4 -(5x^3-7x+4)
= 9x^3+2x^2-5x+4 -5x^3+7x-4
= 4x^2 + 2x^2 + 2x

looks like you are correct

thank you so much!

To find f(x) - g(x), you simply subtract the corresponding terms of the two polynomials. Let's break it down step by step:

Step 1: Subtract the respective coefficients of the same-degree terms:

f(x) = 9x^3 + 2x^2 - 5x + 4
g(x) = 5x^3 - 7x + 4

For the degree 3 terms:
9x^3 - 5x^3 = 4x^3

Step 2: For the degree 2 terms:
2x^2 - 0x^2 = 2x^2

Step 3: For the degree 1 terms:
-5x - (-7x) = -5x + 7x = 2x

Step 4: For the constant terms:
4 - 4 = 0

Now, let's assemble the resulting polynomial:

f(x) - g(x) = 4x^3 + 2x^2 + 2x + 0

So, your answer, 4x^3 + 2x^2 + 2x, is indeed correct. Well done!