Final answer:
The simplified form of the expression 9x^2−5x^4−(5x^3−7x^4) is 9x^2−5x^4−5x^3+7x^4.
Step-by-step explanation:
The simplified form of the expression 9x^2−5x^4−(5x^3−7x^4) is 9x^2−5x^4−5x^3+7x^4.
To simplify the expression, we distribute the negative sign to the terms inside the parentheses. This gives us 9x^2−5x^4−5x^3−(-7x^4). Simplifying further, we can combine like terms, which gives us 9x^2−5x^4−5x^3+7x^4.