The sum of two numbers is 640. If you divide the bigger number by the smaller, you’ll get quotient 7 and remainder 64. Find the numbers.

let 'x' and 'y' represent the two numbers and x>y
The sum of two numbers is 640:
x + y = 640
If you divide the bigger number by the smaller, you’ll get quotient 7 and remainder 64:
x = 7y + 64
by solving the system of equations:
x + y = 640
x = 7y + 64
we find:
x = 568
y = 72