How can i solve for d with the formula is c=rd

1. Inno "Use and to find the estimate" (square root of 9 is 3 and 16 is 4)

2. 39 (square root of 1500 is 38.729...….)

3. -17 (can't be written as a fraction)

4.  A? (I don't know bruh)

5.  (square root of 36 is 6 and 49 is 7, and 47 cant be squared without it being a decimal)

6. -8.5  (  is 8.4   )

7. 12, 167

8. 14

9. If it is rational it can be written as a fraction. So 7/8 is a rational number while π is irrational

10. Finding a cube root for me is harder and takes more steps than finding the square root. To find the square root of 64 is simple. I can do that in my head its 8, but finding the cube root is much harder. So I go one by one till I get to a number that can go into it. 1 is just 1. 2 x 2=4 x 2=8. 3 x 3 = 9 x 3 = 27. 4 x 4 = 16 x 4 = 64