Answer:
1) The system of equations is
and 
2) The first number is
and the second number is 
Step-by-step explanation:
1) Let be "x" the first number and "y" the second number.
Remember that:
a- The word "times" indicates multiplication.
b- A sum is the result of an addition.
c- "Is" indicates this sign: 
Then, the sum of 5 times "x" and 4 times "y" is 75, can written as:

And "The sum of the two numbers is 18" can written as:

Therefore, the System of equations is:

2) You can use the Elimination Method to solve it:
- Multiply the second equation by -5, add the equations and then solve for "y":

- Substitute the value of "y" into any original equation and solve for "x":
