In 7 years, Hyder will be twice as old as he was 8 years ago. How old is he now?

None of these

8 years ago, Hyder's age was x - 8.

7 years from now, Hyder's age will be x + 7.

According to the problem:

x + 7 = 2(x - 8)

Simplify the equation:

x + 7 = 2x - 16

Add 16 to both sides:

x + 23 = 2x

Subtract x from both sides:

23 = x