If

then

Differentiating with respec to
gives


So
is indeed conservative, and

All you need to do is distribute the 8 into each of the terms in the parenthesis.
Your equation will then become
32x + 48y - 24z
Answer: grade 7
Step-by-step explanation:
Grade 7: 20/22 students in club
Grade 8: 20/28 students in club
Grade 7 has higher % of students in science club