How many possible three-digit passwords can be formed using digits 0 through 9 if digits are repeated?

30 ,
720 ,
1,000

The correct option is 3.

Step-by-step explanation:

Total digits 0 to 9 are

0, 1, 2, 3, 4, 5, 6, 7, 8, 9

Total number of digits is 10. It means total possible ways to select the first digit of the password is 10.

Since the reparation is allowed, therefore the possible ways to select the second and third digit of the password is 10.

Total possible ways to form a three-digit passwords is

Therefore the correct option is 3.

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.