A chemical plant manufactures fertilizer. A particular fertilizer recipe calls for 2 units of potash for every 3 units of urea. The potash is shipped to the plant in modular pallets with dimensions (x+6) by (x-2). The urea is shipped to the plant in modular pallets with dimension (x-2) by (x+1). Assuming equal molar density in each product, calculate x such that there is no material left over after manufacturing the fertilizer.