Question

1. $3z - 7z^2 - 5z + 5z^2 + 2z^2$

Explanation:

Step1: Group like terms

Group the \(z^2\) terms and the \(z\) terms together: \((-7z^2 + 5z^2 + 2z^2)+(3z - 5z)\)

Step2: Combine like terms for \(z^2\)

Calculate the sum of the \(z^2\) terms: \(-7z^2+5z^2 + 2z^2=(-7 + 5+2)z^2=0z^2\)

Step3: Combine like terms for \(z\)

Calculate the sum of the \(z\) terms: \(3z-5z=(3 - 5)z=-2z\)

Step4: Combine the results

Since \(0z^2 = 0\), the final result is \(-2z\)

Answer:

\(-2z\)