We can approach this problem by building equations.

Let our integer = y. Then the question stem gives

y = 9a + 3

where a is some other integer.

Statement 1

y = 45b + 30

where b is some other integer. This simplifies to

y=5(9b + 6)

This means that y is divisible by 5, giving a remainder of 0. We can also think about it logically - 45 times any integer is divisible by 5, and 30 is divisible by 5, so 45b + 30 must be divisible by 5. Sufficient.

Statement 2

This tells us that y is even. Let's try some values given what we know from the question stem.

If a = 1, then y = 12, which gives a remainder of 2 when divided by 5. But if x =2, then y = 21, which gives a remainder of 1 when divided by 5, and if x = 3, then 7 = 30, which gives a remainder of 0 when divided by 5. Insufficient.