Let e be the number of emails Mindy has and m be the number of phone messages? We know that e + m = 93 and e = 9m - 7.
Substituting the second equation into the first equation, we get 9m - 7 + m = 93
Combining like terms, we get 10m - 7 = 93
Adding 7 to both sides of the equation, we get 10m = 100
Dividing both sides by 10, we get m = <<10=10>>10
Substituting this value back into the equation e = 9m - 7, we get e = 9 * 10 - 7 = 90 - 7 = 83
#### 83