| 350 | ( | 1 | + | x | ) | ( | 1 | + | x | ) | = | 494 |
| Left side of the equation = | 350 | × | 1 | ( | 1 | + | x | ) | + | 350 | x | ( | 1 | + | x | ) |
| = | 350 | ( | 1 | + | x | ) | + | 350 | x | ( | 1 | + | x | ) |
| = | 350 | × | 1 | + | 350 | x | + | 350 | x | ( | 1 | + | x | ) |
| = | 350 | + | 350 | x | + | 350 | x | ( | 1 | + | x | ) |
| = | 350 | + | 350 | x | + | 350 | x | × | 1 | + | 350 | x | x |
| = | 350 | + | 350 | x | + | 350 | x | + | 350 | x | x |
| = | 350 | + | 700 | x | + | 350 | x | x |
| 350 | + | 700 | x | + | 350 | x | x | = | 494 |