Question

The work of a student to find the dimensions of a rectangle of area 8 + 16x and width 4 is shown below:

Step 1: 8 + 16x
Step 2: 4(4) + 4(12x)
Step 3: 4(4 + 12x)
Step 4: Dimensions of the rectangle are 4 and 4 + 12x

In which step did the student first make an error, and what is the correct step?

Step 3; 4 + (4 + 12x)
Step 3;. 4 + (4 ⋅ 12x)
Step 2; 4(2) + 4(4x)
Step 2; 4(2) + 4x(2)

Answer 1

The student made an error in step 2. It should be 4(2)+4(4x).

Answer 2

Hope this helps :D