Answer:
The the length of the rectangular prism is 6.64 mm
Step-by-step explanation:
knowing the surface area of the rectangular prism is the sum up of all areas of the prisma we have
(20 * 5.9)*2 + (20*X)*2 + (5.9*X)*2 = 733.28
236 + 40X + 34.81X = 733.28
X = 6.64 mm