Answer:
210xy
Explanation:
15x * 14y can be written as 15 * x * 14 * y. Due to the commutative property of multiplication, we can change around the order of these numbers to make this expression easier to understand.
We're going to move the expression around so it is now 15 * 14 * x * y. Now, you can see clearly that you can multiply 15 and 14 together, which will get you 210.
And naturally what you have left is 210 * x * y, which simply appears as 210xy.
I hope this helped!