What is the radical equivalent for 197^7/8?

What is the length of the missing leg in this right triangle? 18 mm 24 mm 26 mm 32 mm

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

What function has a range {yly< 5}? question on picture above^