Question

Bruno claims that the solution to the linear equation
is
. He shows the steps below to justify his solution.

–3(2x + 6) + 25 = 1
Step 1: –6x – 18 + 25 = 1
Step 2: –6x + 7 = 1
Step 3: –6x = –6
Step 4: x = 1

Which of the following statements shows correct reasoning regarding the solution?
Radio button to select the answer below
A.
The solution is incorrect since Step 1 should be
, so the correct solution is x = 7.
Radio button to select the answer below
B.
The solution is incorrect since Step 2 should be
, so the correct solution is

.
C.
The solution is correct since the solution x = 1 follows from the constant shown on the right side of the original equation.
D.
The solution is correct since the solution x = 1 follows from the equality of numbers asserted in each of the previous steps.

Answer 1

D.

Each step is an equivalent transformation of the previous one (correct distribution, combination of like terms, subtracting 7, dividing by -6), so x = 1 is correct.