subtract (3r^4+4r^3)-(r^4-5r^3)

To subtract the given expressions, we need to distribute the negative sign to each term inside the parentheses of the second expression.

So, we have:

(3r^4 + 4r^3) - (r^4 - 5r^3)

Simplifying, we can combine like terms:

= 3r^4 + 4r^3 - r^4 + 5r^3

Now, we can combine the terms with the same exponent:

= (3r^4 - r^4) + (4r^3 + 5r^3)

Simplifying further, we get:

= 2r^4 + 9r^3

Therefore, the subtracted expression is 2r^4 + 9r^3.