Student 1:

Question

f(-1)=2+7(-1)
f(-1)=9(-1)
f(-1)=-9

Student 2:
f(-1)=2+7(-1)
f(-1)=2-7
f(-1)=-5

One student is incorrect. Analyze their work to determine which students work is incorrect and describe the mistakes made.

Answer 1

Student 2's work is incorrect. The mistake was made when they subtracted 7 from 2 instead of multiplying. The correct calculation should be:

f(-1) = 2 + 7(-1)
f(-1) = 2 + (-7)
f(-1) = -5