A rectangle has a length of (4x−3)(4x - 3)(4x−3) cm and a width of (x+6)(x + 6)(x+6) cm.

Find an expression for the perimeter of the rectangle.
Given the rectangle has a perimeter of 31 cm, find the value of xxx.
Practise OCR GCSE Maths Forming and Solving Equations with exam-style questions for Foundation and Higher tier. 78 questions, matched to the OCR GCSE Maths (J560) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.