Hey there :)
Something times

=

Let r represent the unknown
r ×

To find the value of r, take

to the other side by division since the operation performed in multiplication
r =

÷

Since it is a fraction, you can multiply by what is called the reciprocal of the second number divided by
r =

×

The 9's can cancel out since one is in the numerator and the other in the denominator
r =

r = 8
The unknown number is 8