When attempting to do his/her homework, a student uses the addition property of equality to solve for a below. Which statement BEST applies to the sample below?

a + 3 = 9
a + 3 – 3 = 9 – 9
a = 0

Question

When attempting to do his/her homework, a student uses the addition property of equality to solve for a below. Which statement BEST applies to the sample below?

a + 3 = 9
a + 3 – 3 = 9 – 9
a = 0

anonymous · Answer

A.
The student failed to keep both sides of the equation balanced.
B.
The student’s final answer does not have the variable a isolated.
C.
The use of the addition property of equality is sound, and the answer is correct.
D.
The student should have added 3 to the left side of the equation rather than subtracting.