Answer:
(B) Luis's, because he flipped the inequality sign when he subtracted
Explanation:
Let's evaluate each answer choice:
"Amelia's, because the variable term must be isolated on the left side"
This answer choice is wrong! Whichever side the variable term is isolated on DOESN'T affect the answer of the problem.
"Luis's, because he flipped the inequality sign when he subtracted"
This answer choice is right! Only flip the inequality sign when dividing a NEGATIVE number.
"Shauna's, because she did not apply the subtraction property of equality properly"
This answer choice is wrong! Shauna correctly applied the subtraction proper by subtracting 6.5 from both sides.
"Clarence's, because the terms he added together were not like terms"
This answer choice is wrong! Clarence added 8.1 to both sides, so he added 8.1 to 6.5, which are like terms.
Hope it helps (●'◡'●)