Question

Lara solved an equation incorrectly, as shown below:

Step 1: 2x = 18
Step 2: x = 18 − 2
Step 3: x = 16

Which statement best explains why Step 2 is incorrect in Lara's solution?

A) She did not divide 18 by 2.
B)She did not add 2 to 18.
C)She did not multiply 18 by 2.
D) She did not multiply 18 two times.

Answer 1

The answer is b. 18/2=9

Answer 2

We have been given the steps to solve the equation as

Step 1: 2x = 18

Step 2: x = 18 − 2

Step 3: x = 16

There is an error in step 2.

We have
`2x=18`

x is in multiplication with 2. So in order to get rid of 2 from the left hand side, we perform opposite operation of multiplication i.e. division.

So we must divide both sides by 2.

Therefore, A is the correct option.

A) She did not divide 18 by 2.