√77 ≈ 8.7750
√77 is an irrational number, so its decimals never end or repeat. It sits between 8 and 9 because 8² = 64 and 9² = 81.
| Decimal places | Value |
|---|---|
| 0 | 9 |
| 1 | 8.8 |
| 2 | 8.77 |
| 3 | 8.775 |
| 4 | 8.7750 |
| 5 | 8.77496 |
| 10 (digits) | 8.7749643874 |
77 has no perfect-square factor other than 1, so √77 is already in simplest radical form.
8.7750 × 8.7750 ≈ 77.0006, which is very close to 77.
Need another number? Use the square root calculator (also cube roots and other roots).
| Number | Square root |
|---|---|
| 73 | 8.5440 |
| 74 | 8.6023 |
| 75 | 8.6603 |
| 76 | 8.7178 |
| 78 | 8.8318 |
| 79 | 8.8882 |
| 80 | 8.9443 |
| 81 | 9 |