It could be either of two ways:
8 x + 9 or 8 ( x + 9)
You can multiply 9 • 8 because when multiplying, it does not need to be like terms. When you are adding or subtracting monomials, only when it is in like terms can it be simplified.
"The product of 8 and a number y multiplied by 9"
9(8y) is the expression that has been given in word form.
However, as the two constants do not share a common multiple, the expression cannot be simplified further.
8y x 9 ⇒ 72y