Question

I'm stuck. Can anyone help please?

Answer 1

log₉(x - 7) + log₉(x - 7) = 1

2 log₉(x - 7) = 1

log₉(x - 7) = 1/2

Take the base-9 antilogarithm of both sides; in other words, make both sides powers of 9:

`9^(\log_9(x-7)) = 9^(1/2)`

`9^(1/2)` can also be written as √9 = 3, and
`b^(\log_b(a))=a`, so the equation reduces to

x - 7 = 3

Solve for x :

x = 10