Answer:
a² + 5a - 8
Explanation:
If the construction paper has a length of a² + 7a - 3, and Katelyn cut a piece 2a + 5 long, the amount of construction paper that would be left is,
a² + 7a - 3 - (2a + 5)
= a² + 7a - 3 - 2a - 5
collecting like terms, we have
= a² + 7a - 2a - 3 - 5
simplifying, we have
= a² + 5a - 8