A student submitted the following problem

Question

. A student submitted the following problem but the solution is incorrect. • Identify the mistake. What did the student do wrong? • Solve the problem correctly. Sec. 12.5 #72 Subtract (a5 – 1 3 a3 – 5a) from ( 3 4 a5 + 1 2 a4 + 6a). Incorrect solution: (a5 – 1 3 a3 – 5a) - ( 3 4 a5 + 1 2 a4 + 6a) a5 – 1 3 a3 – 5a - 3 4 a5 - 1 2 a4 - 6a 1 4 a5 - 1 2 a4 – 1 3 a3 -11a

Answer 1

a5-13a3-5a minus 34a5+12a4+6a

combine like terms for a5 and a, don't combine a4 and a3

= a5-34a5 -12a4-13a3 -5a-6a

= -33a5-12a4 -13a3 -11a

last answer got it all correct, except the a5 term