Question

The work of a student to find the dimensions of a rectangle of area 8 + 12x and width 4 is shown below:

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

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

Step 2: 4(2) + 4x(2)
Step 2: 4(2) + 4(3x)
Step 3: 4 + (4 + 8x)
Step 3: 4+ (48X)

Answer 1

Step 2: 4 ( 2 ) + 4 ( 3 x )

Explanation:

The student didn't factorise 8 x + 12 properly