Answer:

Explanation:
Taking the first statement and "transcribing" it into an equation:
"The sum of two numbers is 40":

Now the second statement:
"The larger number (x) is 1.5 times the smaller number (y).":

(we don't need to worry about the "larger" and "smaller" part, they are implied by the fact that one is 1.5 larger than the other)
So the system of equations is:
If you are curious: the solution of this system goes as follows:
