7/25 Is 21/75 in simplest form since 7 is a prime number it can't go any further.
By skipping the number for an example skip count by 2 so u go like 2 4 6 8 10 and so on its also how you mulitiply<span />
The n-th term of a geometric sequence with initial value a and common ratio r is given by
.
We have
and
and 
Substitute:

Vertical angles are equal
so
4x + 7 = 5(x - 4)
4x + 7 = 5x - 20
5x - 4x = 7 + 20
x = 27