An odd number under 50 with least 5 factors

Using "^" for powers. I believe the smallest ODD number with exactly 5 factors would be 3^4 = 81. Since you say "at least", we could also consider numbers with 6 factors; the smallest of those would be 3^2 x 5 = 45. So that would be a number under 50.

If x=5 7=8 and z=2 then the new equation in 5+8x2. Following PEMDAS, you multiply 8 and 2 first to get 16 and add 5 and 16  to get the final answer of 21.